Outcome according to KRAS-, NRAS- and BRAF-mutation as well as KRAS mutation variants: pooled analysis of five randomized trials in metastatic colorectal cancer by the AIO colorectal cancer study group

Integrating isothermal amplification techniques and LNA-based AI-assisted electrochemical bioassay for analysis of KRAS G12V point mutation

The KRAS mutation is a crucial biomarker for determining targeted cancer therapies, making its accurate and cost-effective detection vital for precision oncology. However, current methodologies, such as next-generation sequencing (NGS) or PCR-based methods, are often expensive and technically complex, limiting their accessibility. Here, we present a novel bioassay for KRAS G12V mutation analysis that combines rolling circle amplification (RCA) with locked nucleic acid (LNA)-modified magnetic beads, electrochemical detection using carbon electrode chips, and AI-assisted analysis via a logistic regression classifier. Our platform demonstrated exceptional selectivity in distinguishing the KRAS G12V mutation from wild-type (wt) sequences, enabling analysis <1 % of mutated DNA in a wt sample. We validated the bioassay on 7 cancer cell lines and 11 patient-derived samples, achieving results that perfectly correlated with NGS data. This innovative approach simplifies the workflow, reduces costs, and offers high sensitivity and specificity, making it a promising tool for clinical diagnostics and personalized cancer treatment strategies.

Identification of Candidate Alterations Mediating KRASG12C Inhibitor Resistance in Advanced Colorectal and Pancreatic Cancers

PURPOSE

KRAS G12C inhibitors can treat KRASG12C-mutant advanced colorectal cancers and pancreatic ductal adenocarcinomas (PDAC), but alterations in Kirsten rat sarcoma (KRAS), EGFR, BRAF, MAP2K1, and other genes bypass KRAS inhibition and reduce therapy efficacy. Our study evaluates the genetic landscape of candidate primary resistance alterations relevant to KRAS targeting in KRASG12C-mutant colorectal cancer and PDAC.

EXPERIMENTAL DESIGN

We analyzed two cohorts (national database and Mayo) of patients with advanced colorectal cancer or PDAC tested with next-generation sequencing of ctDNA via Guardant360. Cohorts were divided into three groups: KRASG12C alone (KRASG12C without a resistance gene), KRASG12C with resistance (KRASG12C and ≥1 candidate resistance gene), and KRAS not detected. Candidate resistance mutations were inferred from the reported literature.

RESULTS

Among the national (13,603 colorectal cancer and 5,016 PDAC cases) and Mayo (741 colorectal cancer and 422 PDAC cases) cohorts, resistance alterations were identified in a considerable number of KRASG12C cases (46.5% of national colorectal cancer, 16.4% of national PDAC, 53.8% of Mayo colorectal cancer, and 36.4% of Mayo PDAC). The presence of resistance alterations was associated with a trend toward worse overall survival in KRASG12C colorectal cancer (P = 0.05).

CONCLUSIONS

Putative resistance alterations are prevalent in PDAC and colorectal cancer and may limit monotherapy efficacy. Identifying these alterations has potential implications in optimal patient selection for targeted therapies and the development of combination therapy strategies to overcome primary resistance.

Association of Oncogene Driver Mutations with Recurrence and Survival in Stage I Nonsmall Cell Lung Cancer

BACKGROUND

Stage I nonsmall cell lung cancer (NSCLC) is primarily treated with surgical resection and has a favorable prognosis with an expected recurrence rate of 30%. New methods to risk stratify patients with stage I NSCLC are needed to help select those that might benefit from more active surveillance or adjuvant therapy.

METHODS

We analyzed clinical data from 1330 patients (1469 tumors) with NSCLC and correlated it with next-generation sequencing (NGS). To reduce the potential confounding variables of stage and treatment, this analysis only included patients with stage I NSCLC in whom surgical resection was the primary treatment.

RESULTS

In 570 patients (600 tumors), 75 (12.5%) developed recurrence. Recurrence occurred in 37.5% of patients with KRAS G12V mutation versus 11.1% of patients without this mutation (P < .001). A lower chance of recurrence was associated with "any EGFR" mutation (6.74% vs. 14.9%, P = .006). A history of coronary artery disease (CAD) increased the chance of recurrence: OR 2.7 (1.57-4.89, P < .001). Shorter survival was predicted by KRAS G12V (P = .009) and "other TP53" mutation (P = .025). KRAS G12V, KRAS G13D, MET E168D, PTEN, and "other TP53" were oncogene mutations associated with reduced survival in stage I NSCLC. CAD, type 2 diabetes (DM2), and "other cancer" were medical comorbidities associated with reduced survival in stage I NSCLC.

CONCLUSIONS

Oncogene mutations such as KRAS G12V and EGFR may have implications for cancer surveillance strategies and inform future treatment trials of stage I NSCLC.

Onvansertib in Combination With Chemotherapy and Bevacizumab in Second-Line Treatment of KRAS-Mutant Metastatic Colorectal Cancer: A Single-Arm, Phase II Trial

PURPOSE

This phase II study evaluated the efficacy and tolerability of onvansertib, a polo-like kinase 1 (PLK1) inhibitor, in combination with fluorouracil, leucovorin, and irinotecan (FOLFIRI) + bevacizumab for the second-line treatment of KRAS-mutant metastatic colorectal cancer (mCRC).

PATIENTS AND METHODS

This multicenter, open-label, single-arm study enrolled patients with KRAS-mutated mCRC previously treated with oxaliplatin and fluorouracil with or without bevacizumab. Patients received onvansertib (15 mg/m2 once daily on days 1-5 and 15-19 of a 28-day cycle) and FOLFIRI + bevacizumab (days 1 and 15). The primary end point was the objective response rate (ORR), and secondary endpoints included progression-free survival (PFS), duration of response (DOR), and tolerability. Translational and preclinical studies were conducted in KRAS-mutant CRC.

RESULTS

Among the 53 patients treated, the confirmed ORR was 26.4% (95% CI, 15.3 to 40.3). The median DOR was 11.7 months (95% CI, 9.4 to not reached). Grade 3/4 adverse events were reported in 62% of patients. A post hoc analysis revealed that patients with no prior bevacizumab treatment had a significantly higher ORR and longer PFS compared with patients with prior bevacizumab treatment: ORR of 76.9% versus 10.0% (odds ratio of 30.0, P < .001) and median PFS of 14.9 months versus 6.6 months (hazard ratio of 0.16, P < .001). Our translational findings support that prior bevacizumab exposure contributes to onvansertib resistance. Preclinically, we showed that onvansertib inhibited the hypoxia pathway and exhibited robust antitumor activity in combination with bevacizumab through the inhibition of angiogenesis.

CONCLUSION

Onvansertib in combination with FOLFIRI + bevacizumab showed significant activity in the second-line treatment of patients with KRAS-mutant mCRC, particularly in patients with no prior bevacizumab treatment. These findings led to the evaluation of the combination in the first-line setting (ClinicalTrails.gov identifier: NCT06106308).

Mortality Outcome Associated with Specific KRAS, NRAS, and BRAF Hot-Spot Mutations in Metastatic Colorectal Cancer Patients: A Retrospective Cohort Study

Background/Objective: The prognostic value of specific hot-spot mutations within KRAS, NRAS, and BRAF genes in metastatic colorectal cancer (mCRC) genes remains debatable. This study explores whether certain KRAS, NRAS, and BRAF mutations are associated with the risk of all-cause mortality in mCRC. Methods: We retrospectively analyzed records of 494 patients with mCRC treated at the University of Texas Medical Branch between January 2016 and July 2023. Data on genetic mutations and clinicopathological features were collected for this analysis. We estimated survival probabilities and conducted multivariable Cox proportional hazards regression to evaluate the impact of specific mutations on all-cause mortality risk. Results:KRAS c.35G>T (p.Gly12Val) and c.34G>T (p.Gly12Cys) mutations were significantly associated with an increased risk of all-cause mortality in the overall mCRC population and the treated mCRC subgroup. KRAS c.38G>A (p.Gly13Asp) was significantly associated with an increased risk of all-cause mortality in the treated mCRC subgroup but BRAF c.1799T>A (p.Val600Glu) was significantly associated with an increased risk of all-cause mortality in the overall mCRC population. No significant association was observed between NRAS mutations and mortality risk in mCRC, possibly due to their lower frequency or different biological effects compared to KRAS and BRAF mutations. Conclusions: These findings suggest that specific KRAS [c.35G>T (p.Gly12Val), c.34G>T (p.Gly12Cys), and c.38G>A (p.Gly13Asp)] and BRAF c.1799T>A (p.Val600Glu) mutations may have prognostic value in mCRC. However, given the single-center study design and lack of direct therapeutic implications, larger multicenter studies are needed to substantiate these results and better define the clinical relevance of these mutations.

A Narrative Review of RAS Mutations in Early-Stage Colorectal Cancer: Mechanisms and Clinical Implications

Colorectal cancer (CRC) is the third-most common cancer globally and a leading cause of cancer-related deaths. While the prognostic and predictive roles of RAS mutations in advanced CRC are well-established, their significance in early-stage CRC remains a topic of debate. Studies have been conducted for many years on clinical and pathological parameters that may be associated with RAS mutation, and there are inconsistent results in this regard. Currently, the only biomarker used in early-stage CRC is microsatellite status. KRAS mutations are detected in 40-50% of patients with colorectal cancer. RAS activating mutations cause loss of EGFR regulation by acting on the RAS/RAF/MAPK signaling pathways. In advanced colorectal cancer, these mechanisms cause a decrease in the effectiveness of EGFR inhibitors. However, studies on patients with early-stage colorectal cancer have inconsistent results. This review highlights the prognostic and clinical significance of KRAS mutations in early-stage CRC, particularly in MSS tumors. In the MSS group, KRAS mutations were associated with shorter TTR and OS compared to DWT patients. In contrast, in the MSI-H group, KRAS mutations showed no prognostic effect in TTR and OS. However. KRAS mutations were associated with shorter SAR in both MSI-H and MSS groups of patients. The findings underscore the need for routine molecular profiling, including KRAS and MSI status, to refine risk stratification and guide adjuvant therapy decisions. Further studies are warranted to explore targeted therapeutic approaches for KRAS-mutant CRC in the adjuvant setting.

Genome-wide CRISPR screening identifies PHF8 as an effective therapeutic target for KRAS- or BRAF-mutant colorectal cancers

BACKGROUND

Mutations in KRAS and BRAF genes are prevalent in colorectal cancer (CRC), which strikingly promote tumorigenesis and lead to poor response to a variety of treatments including immunotherapy by activating the MAPK/ERK pathway. Thus, there is an urgent need to discover effective therapeutic targets and strategies.

METHODS

CRISPR-Cas9 lentiviral knockout library was used to screen the suppressors of anti-PD1 immunotherapy. Bioinformatic analysis was used to analyze the correlation between PHF8 expression and immune indicators in CRC. In vitro and in vivo experiments were utilized to determine the effects of PHF8 on the immune indexes and malignant phenotypes of CRC cells. qRT-PCR, western blotting, immunohistochemical (IHC) staining, and chromatin immunoprecipitation (ChIP)-qPCR assays were used to determine the regulatory effects of PHF8 on PD-L1, KRAS, BRAF, and c-Myc and the regulatory effect c-Myc/miR-22-3p signaling axis on PHF8 expression in CRC cells.

RESULTS

This study identified histone lysine demethylase PHF8 as a negative regulator for the efficacy of anti-PD1 therapy and found that it was highly expressed in CRCs and strongly associated with poor patient survival. Functional studies showed that PHF8 played an oncogenic role in KRAS- or BRAF-mutant CRC cells, but not in wild-type ones. Mechanistically, PHF8 up-regulated the expression of PD-L1, KRAS, BRAF, and c-Myc by increasing the levels of transcriptional activation marks H3K4me3 and H3K27ac and decreasing the levels of transcriptional repression mark H3K9me2 within their promoter regions, promoting immune escape and tumor progression. Besides, our data also demonstrated that PHF8 was up-regulated by the c-Myc/miR-22-3p signaling axis to form a positive feedback loop. Targeting PHF8 substantially improved the efficacy of anti-PD1 therapy and inhibited the malignant phenotypes of KRAS- or BRAF-mutant CRC cells.

CONCLUSION

Our data demonstrate that PHF8 may be an effective therapeutic target for KRAS- or BRAF-mutant CRCs.

Comparative efficacy of cetuximab combined with FOLFOX or CAPEOX in first-line treatment of RAS/BRAF wild-type metastatic colorectal cancer: a multicenter case-control study

FOLFOX combined with cetuximab is a recommended first-line treatment regimen for RAS/BRAF wild-type metastatic colorectal cancer (mCRC). CAPEOX combined with cetuximab differs from the FOLFOX regimen by using oral capecitabine instead of continuous infusion of fluorouracil, offering greater convenience and cost-effectiveness with higher patient acceptance. However, the comparative efficacy of these two regimens remains debatable, necessitating further evidence to explore any differences in their efficacy. This study collected medical records of mCRC patients who were treated with CAPEOX or FOLFOX combined with cetuximab from 1 October 2021 to 16 October 2023 at Harbin Medical University Cancer Hospital and the First Hospital of Shanxi Medical University. Eligible patients were selected based on inclusion criteria and followed up through the hospital's follow-up system and telephone interviews. Kaplan-Meier survival analysis and Cox proportional hazards regression analysis were used to assess patients' progression-free survival (PFS) and overall survival (OS). A total of 71 eligible patients were enrolled in this study; 43 patients received CAPEOX combined with cetuximab (Group A, n = 43), and 28 patients received FOLFOX combined with cetuximab (Group B, n = 28). The two groups achieved similar median PFS (mPFS) and median OS (mOS), with mPFS of 18 months and 12 months, respectively (P = 0.23), and mOS of 33 months and 20 months, respectively (P = 0.21), with no statistically significant differences. The results of this study demonstrated that CAPEOX combined with cetuximab is an equally viable option for first-line treatment of RAS/BRAF wild-type mCRC as FOLFOX combined with cetuximab.

Effect of RAS mutations and related immune characteristics on the prognosis of patients with MSI-H/dMMR colorectal cancer

PURPOSE

Microsatellite high instability/deficient mismatch repair (MSI-H/dMMR) colorectal cancer (CRC) has an active tumor microenvironment, rendering it more sensitive to immune checkpoint inhibitors. Given that studies involving patients with MSI-H colorectal cancer with RAS mutations are scarce, we explored the effect of RAS mutations on the TME in patients with MSI-H/dMMR cancer and identified potential prognostic factors.

METHODS

Seventy-five patients diagnosed with MSI-H/dMMR colorectal cancer were retrospectively enrolled and divided into RAS-mutant and -wild-type groups. The expression levels of CD11c+ dendritic cells, CD4+ T cells, CD8+ T cells, and regulatory T cell (Treg) markers were detected, and prognostic factors were analyzed.

RESULTS

RAS-mutant MSI-H colorectal patients were more likely to have: (1) higher platelet values; (2) shorter disease-free survival (DFS); (3) lower infiltrated numbers of CD11c+ dendritic cells, CD4+ T lymphocytes, and CD8+ T lymphocytes, and higher infiltrated numbers of Foxp3+ Treg cells. In MSI-H/dMMR CRC patients: (1) the high CD11c + , CD4 +,  and CD8 +  cells infiltration group had longer DFS than the low-infiltration group, and Foxp3 + cells infiltration was not significantly correlated with DFS; (2) the RAS mutation status, number of CD11c+ cells infiltrated, and carbohydrate antigen 19-9 (CA19-9) level were the potential prognostic factors.

CONCLUSION

RAS mutations in patients with MSI-H/dMMR CRC may reduce the infiltration of CD11c+ dendritic cells, CD4+ T cells, and CD8+ T cells, and increase the infiltration of Foxp3+ Treg cells to affect the tumor microenvironment of patients. RAS gene status, CD11c + cells infiltration, and CA19-9 level were potential prognostic factors for MSI-H/dMMR CRC.

MRTX1133 attenuates KRASG12D mutated-colorectal cancer progression through activating ferroptosis activity via METTL14/LINC02159/FOXC2 axis

Colorectal cancer (CRC) ranks as the third most commonly diagnosed cancer and the second leading cause of cancer-related deaths worldwide. Studies have shown that CRC patients with KRAS mutations, especially KRASG12D, have an increased risk of metastasis. Emerging evidence indicates that long non-coding RNAs (lncRNAs) are crucial in the carcinogenesis and progression of various cancers, regulating multiple biological processes but the link between KRASG12D mutations and lncRNAs in CRC remains unclear. Therefore, this study was designed to identify a novel lncRNA involved in KRASG12D-mutated CRC and to elucidate its molecular mechanisms. The analysis of differentially expressed lncRNAs in the GSE201412 dataset revealed that LINC02159 was significantly upregulated following treatment with the KRASG12D inhibitor MTRX1133 Data from the GTEx database indicated that LINC02159 is highly expressed in CRC tumour tissues and is associated with better patient outcomes. In vitro and in vivo experiments suggest that LINC02159 acts as a tumour suppressor in CRC progression. Specifically, LINC02159 knockdown negated the inhibitory effects of MRTX1133 on tumourigenesis and its promotive effect on ferroptosis in KRASG12D-mutated CRC cells. LINC02159 expression is regulated by METTL14, with METTL14 knockdown decreasing m6A methylation of LINC02159, leading to its increased expression in CRC cells. Additionally, LINC02159 stabilised FOXC2 expression through de-ubiquitination. Rescue experiments further clarified that the METTL14/LINC02159/FOXC2 signalling axis is crucial for the inhibitory effects of MRTX1133 in KRASG12D-mutated CRC. Our study provides novel insights into the therapeutic potential of MRTX1133 in treating KRASG12D-mutated CRC by identifying a METTL14/LINC02159/FOXC2 signalling axis that mediates drug response. Our findings highlight the importance of understanding the molecular mechanisms of lncRNAs in cancer to develop effective targeted therapies.

Discovery of a tribenzophenazine analog for binding to the KRAS mRNA G-quadruplex structures in the cisplatin-resistant non-small cell lung cancer

Lung cancer is the malignant tumor with the highest morbidity and mortality rate worldwide, of which non-small cell lung cancer (NSCLC) accounts for approximately 85%. KRAS mutations are one of the significant mechanisms underlying the occurrence, development, immune escape, and chemotherapy resistance of NSCLC. Two KRAS inhibitors are approved by Food and Drug Administration for the treatment of NSCLC in the past 3 years. However, they are only effective to KRAS G12C mutant, and moreover, innate and acquired drug resistance is already reported, leaving an urgent need to block KRAS pathways through novel targets. In this study, we focused on the discovery of ligands targeting the RNA G-quadruplexes in 5'-UTR of KRAS mRNA, and a novel tribenzophenazine analog (MBD) was identified as the lead compound. Further mechanisms were discussed in A549/DDP cells, a cisplatin-resistant and KRAS-mutant NSCLC cell line. Antitumor efficacy was verified both in vitro in A549/DDP cells, and in vivo in a nude mouse xenograft model implanted with A549/DDP cells. To sum up, our results suggest the potential of MBD as a prominent anti-KRAS-driven NSCLC agent and propose a new idea for the development of small molecule ligands targeting KRAS RNA G-quadruplexes.

HDAC and MEK inhibition synergistically suppresses HOXC6 and enhances PD-1 blockade efficacy in BRAFV600E-mutant microsatellite stable colorectal cancer

BACKGROUND

B-Raf proto-oncogene, serine/threonine kinase (BRAF)V600E-mutant microsatellite stable (MSS) colorectal cancer (CRC) constitutes a distinct CRC subgroup, traditionally perceived as minimally responsive to standard therapies. Recent clinical attempts, such as BRAF inhibitors (BRAFi) monotherapy and combining BRAFi with other inhibitors, have yielded unsatisfactory efficacy. This study aims to identify a novel therapeutic strategy for this challenging subgroup.

METHODS

We first performed a large-scale drug screening using patient-derived organoid models and cell lines to pinpoint potential therapies. Subsequently, we investigated the synergistic effects of identified effective inhibitors and probed their cooperative mechanisms. Concurrently, we explored the immune characteristics of BRAFV600E MSS CRC using RNA sequencing and multiplex immunohistochemistry. Finally, we established a CT26 BRAFV637E mouse cell line and validated the efficacy of combining these inhibitors and programmed death 1 (PD-1) blockades in immunocompetent mice.

RESULTS

Drug screening identified histone deacetylase (HDAC) inhibitor and mitogen-activated protein kinase kinase (MEK) inhibitor as significantly effective against BRAFV600E MSS CRC. Further research revealed that these two inhibitors have superior synergistic effects by comprehensively inhibiting the activation of the epidermal growth factor receptor, mitogen-activated protein kinase, and phosphoinositide 3-kinase-protein kinase B pathways and suppressing the key target homeobox C6 (HOXC6). HOXC6, overexpressed in BRAFV600E MSS CRC, regulates the MYC gene and contributes to treatment resistance, tumor growth, and metastasis. Moreover, the combination therapy demonstrated the ability to enhance antitumor immunity by synergistically upregulating the expression of immune activation-related genes, activating the cyclic guanosine monophosphate-adenosine monophosphate synthase/stimulator of interferon genes (cGAS/STING) pathway, and diminishing the tumor cells' DNA mismatch repair capacity. Notably, BRAFV600E MSS CRC was identified to exhibit a distinct immune microenvironment with increased PD-1+ cell infiltration and potential responsiveness to immunotherapy. Echoing the above findings, in vivo, HDAC and MEK inhibitors significantly improved PD-1 blockade efficacy, accompanied by increased CD8+ T-cell infiltration.

CONCLUSIONS

Our findings indicate that combining HDAC inhibitor, MEK inhibitor, and PD-1 blockade is a potential strategy for treating BRAFV600E-mutant MSS CRC, warranting further investigation in clinical settings.

Comprehensive data of 5085 patients newly diagnosed with colorectal liver metastasis between 2013 and 2017: Fourth report of a nationwide survey in Japan

The Joint Committee for Nationwide Survey on colorectal liver metastasis (CRLM) was established to improve treatment outcomes in patients with CRLM. The aim of this study was to evaluate the transition in the characteristics and treatment strategies of patients with CRLM and to analyze the prognostic factors. The data of 5085 patients newly diagnosed between 2013 and 2017 were compared with those of 3820 patients from 2005 and 2007. In patients who underwent hepatectomy (n = 2759 and 2163), the number of CRLMs was significantly higher and in the 2013-2017 data than in the 2005-2007 data (median 2 vs. 1; p = .005). Overall survival (OS) rates after diagnosis of CRLM after hepatectomy were better in the 2013-2017 data than that in the 2005-2007 data (5-year OS, 62.4% vs. 56.7%, p < .001). Recurrence-free survival (RFS) after hepatectomy was comparable between the groups (5-year RFS, 30.5% vs. 30.7%; p = .068). Multivariate analyses identified age at diagnosis of CRLM ≥70 years, lymph node metastasis of primary lesion, preoperative carbohydrate antigen (CA) 19-9 value >100 U/mL, number of CRLM 2-4, and R2 resection as independent predictors of OS. Synchronous CRLM, concomitant extrahepatic metastasis, lymphatic invasion, lymph node metastasis of primary lesion, preoperative CA19-9 value >100 U/mL, number of CRLM 5-, and nonlaparoscopic approach were selected as that of RFS. Despite having a higher prevalence of advanced stage CRLM in the 2013-2017 patient population compared to the 2005-2007 cohort, prognostic outcomes demonstrably improved in the later period.

Adagrasib in the Treatment of KRAS p.G12C Positive Advanced NSCLC: Design, Development and Place in Therapy

One of the most common mutations seen in lung cancers are mutations in Kristen Rat Sarcoma Viral Oncogene Homolog (KRAS), observed in 25-30% of patients with NSCLC. Mutations in KRAS result in oncogenesis via persistent activation of the MAPK/ERK pathways. Although once thought to be "undruggable", KRAS p.G12C inhibitors such as sotorasib and adagrasib have been developed. This paper focuses on adagrasib, the second KRAS p.G12C inhibitor to obtain regulatory approval by the FDA and describes the details on its study design, development and current place in therapy.

Systemic inflammatory response in colorectal cancer is associated with tumour mismatch repair and impaired survival

The systemic inflammatory response (SIR), defined as elevated levels of circulating C-reactive protein (CRP), is an important predictor of impaired survival in colorectal cancer. The aim of this study was to explore the prognostic role of SIR and its association with tumour mismatch repair status and the immune response. Immune activity profiles of mononuclear cells isolated from CRC tissues and blood in the U-CAN exploration cohort (n = 69), were analysed by flow cytometry. In the U-CAN validation cohort (n = 257), T-helper cells (T-bet+), cytotoxic T cells (CD8+), regulatory T cells (FoxP3+), B cells (CD20+), and macrophages (CD68+) were analysed by multispectral imaging. Microsatellite instability was determined using five mononucleotide-repeat microsatellite markers. Patients with high CRP levels (> 10 mg/l) were significantly more often diagnosed with high-grade tumours and tumours exhibiting microsatellite instability. However, some patients with high CRP levels were found to have microsatellite-stable tumours. Furthermore, high CRP levels were associated with specific tumour immune traits including an augmented macrophage response and were significantly linked to poorer cancer-specific survival, particularly in patients with microsatellite-stable tumours. In conclusion, our findings suggest an interplay between SIR and mismatch repair status in CRC prognosis which needs to be further explored.

Exploring the molecular profile of localized colon cancer: insights from the AIO Colopredict Plus registry

Introduction

Understanding the mutational landscape of colon cancer (CC) is crucial for targeted therapy development. Microsatellite instability (MSI-H), rat sarcoma (RAS), and B-Raf proto-oncogene, serine/threonine kinase (BRAF) mutations (MT) are pivotal markers. Further investigation into clinicopathological features of RAS and BRAF MT in microsatellite stable (MSS) and MSI-H tumors is warranted.

Methods

A retrospective analysis of 4883 localized CC patients (pts.) was conducted. Molecular profiling assessed MSI, KRAS, NRAS, and BRAF MT. Correlation with clinicopathological data employed ANOVA and Chi-square tests. Disease-free survival (DFS) and overall survival (OS) were analyzed adjusting for age, gender, sidedness, UICC stage, Charlson Comorbidity Index (CCI). A Cox model incorporated all variables as covariates.

Results

This analysis included 4883 pts. (2302 female/2572 male, 3865 (79.2%) MSS, 1018 (20.8%) MSI-H). MSS pts. had more All-Wild Type (WT), KRAS MT, and NRAS MT tumors vs. MSI-H pts. (42.1% vs. 21.1%; 39.8% vs. 15.4%; 3.6% vs. 0.7%; p<0.001 for each). BRAF MT tumors (95.5% BRAF V600E MT) were more prevalent in MSI-H individuals (62.8% vs. 8.1%, p<0.001). KRAS and BRAF MT tumors were more frequently right-sided, while BRAF MT tumors were associated with female gender, advanced disease stage, lymph node positivity, and poorer differentiation in the MSS subset (p<0.001). Common KRAS mutations included p.G12D (30.44%) and p.G12V (21.3%) in MSS and p.G13D (28.9%) and p.G12D (22.37%) in MSI-H. NRAS MT tumors were dominated by codon 61 mutations (51.7%). Survival analysis revealed worst prognosis in BRAF MT MSS tumors (DFS: HR 1.74 (95% CI 1.15-2.62, p=0.009; OS: HR 1.61 (95% CI 0.99-2.6), p=0.055). The 3-years DFS and 5-years OS rates were lowest in this subset (61.6% and 57.7% respectively).

Discussion

These findings highlight the complex interplay between molecular subtypes, clinicopathological features, and survival outcomes in early CC. Further research is needed to elucidate underlying mechanisms and develop personalized treatment strategies.

Molecular, Socioeconomic, and Clinical Factors Affecting Racial and Ethnic Disparities in Colorectal Cancer Survival

Importance

Disparity in overall survival (OS) and differences in the frequency of driver gene variants by race and ethnicity have been separately observed in patients with colorectal cancer; however, how these differences contribute to survival disparity is unknown.

Objective

To quantify the association of molecular, socioeconomic, and clinical covariates with racial and ethnic disparities in overall survival among patients with colorectal cancer.

Design, Setting, and Participants

This single-center cohort study was conducted at a tertiary-level cancer center using relevant data on all patients diagnosed with colorectal cancer from January 1, 1973, to March 1, 2023. The relative contribution of variables to the disparity was determined using mediation analysis with sequential multivariate Cox regression models.

Main Outcome

OS, from diagnosis date and from start of first-line chemotherapy.

Results

The study population of 47 178 patients (median [IQR] age, 57.0 [49-66] years; 20 465 [43.4%] females and 26 713 [56.6%] males; 3.0% Asian, 8.7% Black, 8.8% Hispanic, and 79.4% White individuals) had a median (IQR) follow-up from initial diagnosis of 124 (174) months and OS of 55 (145) months. Compared with White patients, Black patients had worse OS (hazard ratio [HR], 1.16; 95% CI, 1.09-1.24; P <.001), whereas Asian and Hispanic patients had better OS (HR, 0.66; 95% CI, 0.59-0.74; P <.001; and 0.86; 95% CI, 0.81-0.92; P <.001, respectively). When restricted to patients with metastatic disease, the greatest disparity was between Black patients compared with White patients (HR, 1.2; 95% CI, 1.06-1.37; P <.001). Evaluating changes in OS disparity over 20 years showed disparity decreasing among Asian, Hispanic, and White patients, but increasing between Black patients and White patients (HRs, 1.18; 95% CI, 1.07-1.31 for 2008-2012; 1.24, 95% CI, 1.08-1.42 for 2013-2017; and 1.50; 95% CI, 1.20-1.87 for 2018-2023). Survival outcomes for first-line chemotherapy were worse for Black patients compared with White patients (median OS, 18 vs 26 months; HR, 1.30; 95% CI, 1.01-1.70). Among 7628 patients who had clinical molecular testing, APC, KRAS, and PIK3CA showed higher variant frequency in Black patients (false discovery rate [FDR], 0.01; < 0.001; and 0.01, respectively), whereas BRAF and KIT were higher among White patients (FDR, 0.001 and 0.01). Mediation analysis identified neighborhood socioeconomic status as the greatest contributor to OS disparity (29%), followed by molecular characteristics (microsatellite instability status, KRAS variation and BRAF variation, 10%), and tumor sidedness (9%).

Conclusions

This single-center cohort study identified substantial OS disparity and differing frequencies of driver gene variations by race and ethnicity. Socioeconomic status had the largest contribution but accounted for less than one-third of the disparity, with substantial contribution from tumor molecular features. Further study of the associations of genetic ancestry and the molecular pathogenesis of colorectal cancer with chemotherapy response is needed.

KRASG12D-Mutated Metastatic Colorectal Cancer: Clinical, Molecular, Immunologic, and Prognostic Features of a New Emerging Targeted Alteration

PURPOSE

KRASG12D mutation (mut) occurs in about 10%-12% of metastatic colorectal cancer (mCRC). Recently, novel KRASG12D inhibitors have been developed and are currently under investigation in phase I/II clinical trials in solid tumors including mCRC. We aimed at performing a comprehensive characterization of clinical, molecular, immunologic, and prognostic features of KRASG12D-mutated mCRC to inform the design and the interpretation of future trials.

METHODS

We performed a pooled analysis of phase III TRIBE and TRIBE2 studies comparing 5-fluorouracil, leucovorin, oxaliplatin, and irinotecan (FOLFOXIRI)/bevacizumab (bev) to doublets (5-fluorouracil, leucovorin, and oxaliplatin or 5-fluorouracil, leucovorin, and irinotecan)/bev.

RESULTS

One hundred and thirty-six (16%) of 854 patients with available KRASG12D mutational status were KRASG12D mutated. KRASG12D-mutated patients had more frequently right-sided primary tumor and were less likely to present liver-only metastases with respect to other RAS mutated and all-wild-type (wt) patients. Compared with the BRAFV600E-mutated group, KRASG12D-mutated patients had more frequently left-sided primary tumor, resected primary tumor at the time of diagnosis, and Eastern Cooperative Oncology Group performance status 0. KRASG12D-mutated patients had better prognosis than BRAFV600E-mutated and worse prognosis than all wt patients. No prognostic difference was evident between KRASG12D mut and other RAS mut patients overall or according to other specific KRAS or NRAS hotspot mutations. No interaction effect was observed between KRASG12D mut and the benefit provided by FOLFOXIRI/bev compared with doublets/bev. PIK3CA mut were reported more frequently among KRASG12D-mutated tumors compared with both other RAS mut and all wt.

CONCLUSION

A detail estimation of KRASG12D mut mCRC patients' characteristics and expected outcomes may be useful when planning future studies in this subgroup. The high prevalence of PI3K/PTEN/Akt pathway activating alterations may affect the efficacy of targeted strategies.

Iron homeostasis and ferroptosis in human diseases: mechanisms and therapeutic prospects

Iron, an essential mineral in the body, is involved in numerous physiological processes, making the maintenance of iron homeostasis crucial for overall health. Both iron overload and deficiency can cause various disorders and human diseases. Ferroptosis, a form of cell death dependent on iron, is characterized by the extensive peroxidation of lipids. Unlike other kinds of classical unprogrammed cell death, ferroptosis is primarily linked to disruptions in iron metabolism, lipid peroxidation, and antioxidant system imbalance. Ferroptosis is regulated through transcription, translation, and post-translational modifications, which affect cellular sensitivity to ferroptosis. Over the past decade or so, numerous diseases have been linked to ferroptosis as part of their etiology, including cancers, metabolic disorders, autoimmune diseases, central nervous system diseases, cardiovascular diseases, and musculoskeletal diseases. Ferroptosis-related proteins have become attractive targets for many major human diseases that are currently incurable, and some ferroptosis regulators have shown therapeutic effects in clinical trials although further validation of their clinical potential is needed. Therefore, in-depth analysis of ferroptosis and its potential molecular mechanisms in human diseases may offer additional strategies for clinical prevention and treatment. In this review, we discuss the physiological significance of iron homeostasis in the body, the potential contribution of ferroptosis to the etiology and development of human diseases, along with the evidence supporting targeting ferroptosis as a therapeutic approach. Importantly, we evaluate recent potential therapeutic targets and promising interventions, providing guidance for future targeted treatment therapies against human diseases.

Development and validation of a clinical prognostic model for BRAF V600E-mutated colorectal cancer patients based on pathological stage, microsatellite status, and primary tumor site

Objective

To develop and validate a prognostic model for patients with BRAF V600E-mutated colorectal cancer.

Methods

The clinical and pathological information of 206 patients with BRAF V600E-mutated colorectal cancer diagnosed in Cancer Hospital, Chinese Academy of Medical Sciences, and Peking Union Medical College from 2014 to 2021 was retrospectively collected. Least absolute shrinkage and selection operator (LASSO) regression, Cox regression, and nomograms were used to develop clinical prognostic models. The differentiation was measured using C-statistic, and the predicted variability was evaluated using the calibration curve. The prognostic model was externally validated using validation set data from 164 patients pooled from five studies.

Results

Our clinical prognostic model included three variables: pathological stage, microsatellite status, and primary tumor site. In internal validation, the model had a concordant index of 0.785 (95% CI [0.732-0.839]) and a concordant index of 0.754 (95% CI [0.698-0.810]) using pathological staging. External validation confirmed the robustness of the model with a consistency index of 0.670 (95% CI [0.617-0.724]) and a consistency index of 0.584 (95% CI [0.546-0.622]) using pathological staging. Likelihood ratio test results show that our model is better (internal validation, p = 5.141e-03; external validation, p = 2.728e-05). The calibration graph drawn based on the prediction and the actual situation is close to the 45° diagonal.

Conclusion

By adding microsatellite status and primary tumor site on the basis of pathological stage, we improved the discriminability and prediction accuracy of the model and successfully established a prognosis model for patients with BRAF V600E mutation of colorectal cancer.

Evaluation of the prognostic effectiveness of liver metastasis volume by volumetric measurement in colorectal cancer

Aim: To evaluate the relationship between liver metastasis volume and survival in colorectal cancer patients using the volumetric measurement method.Methods: 114 colorectal cancer patients with isolated liver metastases were included in the study. Liver tumor volume, total liver volume were calculated from the patients images at the time of diagnosis. Vitrea 7.14 imaging software was used for liver volume analysis and volume analysis of each metastasis.Results: Median overall survival(OS) in the group with tumor volume <42 ml3 was 30.98 months In the group with tumor volume ≥42 ml3, median OS was 16.36 months (p: 0.001). In patients who underwent metastasectomy, the median OS in the group with a tumor volume <42 ml3 was 52.3 months, the median OS in the group with a tumor volume ≥42 ml3 was 22.2 months. In patients who did not undergo metastasectomy, the median OS in the <42 ml3 group was 20.23 months, the median OS in the ≥42 ml3 group was 15.63 months.Conclusion: In our study, we found that liver metastasis volume was prognostic for OS. It is argued that tumor volume measurement by volumetric measurement is a widely used method in the decision for metastasectomy in liver metastatic colorectal cancer patients.

MRI T2WI-based radiomics combined with KRAS gene mutation constructed models for predicting liver metastasis in rectal cancer

BACKGROUND

The study aimed to identify the optimal model for predicting rectal cancer liver metastasis (RCLM). This involved constructing various prediction models to aid clinicians in early diagnosis and precise decision-making.

METHODS

A retrospective analysis was conducted on 193 patients diagnosed with rectal adenocarcinoma were randomly divided into training set (n = 136) and validation set (n = 57) at a ratio of 7:3. The predictive performance of three models was internally validated by 10-fold cross-validation in the training set. Delineation of the tumor region of interest (ROI) was performed, followed by the extraction of radiomics features from the ROI. The least absolute shrinkage and selection operator (LASSO) regression algorithm and multivariate Cox analysis were employed to reduce the dimensionality of radiomics features and identify significant features. Logistic regression was employed to construct three prediction models: clinical, radiomics, and combined models (radiomics + clinical). The predictive performance of each model was assessed and compared.

RESULTS

KRAS mutation emerged as an independent predictor of liver metastasis, yielding an odds ratio (OR) of 8.296 (95%CI: 3.471-19.830; p < 0.001). 5 radiomics features will be used to construct radiomics model. The combined model was built by integrating radiomics model with clinical model. In both the training set (AUC:0.842, 95%CI: 0.778-0.907) and the validation set (AUC: 0.805; 95%CI: 0.692-0.918), the AUCs for the combined model surpassed those of the radiomics and clinical models.

CONCLUSIONS

Our study reveals that KRAS mutation stands as an independent predictor of RCLM. The radiomics features based on MR play a crucial role in the evaluation of RCLM. The combined model exhibits superior performance in the prediction of liver metastasis.

CLINICAL TRIAL NUMBER

Not applicable.

Association of various RAS codon mutations and prognostic outcomes of patients with colorectal liver metastases after hepatectomy

PURPOSE

The prognostic and predictive value of RAS mutations in patients with colorectal liver metastases (CRLM) who have undergone hepatectomy holds substantial importance. The present study aimed to investigate the impact of different RAS codon mutations on long-term survival in CRLM patients.

METHODS

A retrospective analysis was conducted on clinicopathological data from 399 CRLM patients with RAS mutations who underwent hepatectomy between January 2000 and December 2020. The RAS mutation gene status was assessed in KRAS codons (G12, G13, Q61, and A146) and NRAS codons (G12, G13, and Q61). Survival curves were generated using the Kaplan-Meier plotter and compared using the log-rank test. Univariate and multivariate analyses were performed to analyze the clinicopathological data.

RESULTS

In the entire cohort, patients with KRAS G12 mutations exhibited the most favorable prognosis (p = 0.018). Comparatively, patients harboring KRAS Q61 mutations experienced poorer overall survival (OS) with a median of 15 months versus 33 months (p = 0.011) when compared to those with KRAS G12 mutations. Moreover, patients with NRAS Q61 mutations also showed decreased OS with a median of 26 months versus 33 months (p = 0.020) in comparison to KRAS G12 mutation patients. The results of multivariate analysis showed that both KRAS Q61 mutation (HR 2.130; 95% CI 1.088-4.168; p = 0.027) and NRAS Q61 mutation (HR 2.877; 95% CI 1.398-5.922; p = 0.004) were independent influencing factors of OS. Based on all identified risk factors, patients with RAS mutation were divided into high-risk and low-risk groups. Notably, in the high-risk group, the incorporation of postoperative chemotherapy was associated with longer OS, while it did not improve the survival of patients in the low-risk group.

CONCLUSIONS

KRAS Q61 and NRAS Q61 mutations are promising predictors for OS in CRLM patients after hepatectomy. Postoperative chemotherapy may significantly benefit CRLM patients with RAS mutations, particularly those identified as high-risk.

Associations of KRAS Mutations and Clinical Characteristics of Colorectal Cancer Patients in Indonesia

BACKGROUND

Colorectal cancer (CRC) remains a major burden worldwide, ranking third and second in incidence and mortality respectively. Detection of biomarkers including KRAS mutations can help predict prognosis and response to therapy in CRC, thus this study evaluated the frequency of KRAS mutations among Indonesian patients and their associations with clinicopathologic characteristics.

METHODS

Fifty-three CRC samples were collected from January to September 2022 in the Department of Surgery, Dr. Hasan Sadikin General Hospital, Bandung, Indonesia. KRAS mutations were analyzed using PCR followed by Sanger sequencing. Associations between KRAS mutations were evaluated using binary logistic regression analysis.

RESULT

KRAS mutations were detected in 52.8% of patients (n=28), of which 3.6% were p.Gly12Ser (n=1), 32.1% were p.Gly12Asp (n=9), 7.1% were p.Gly13Asp (n=2), 3.6% were p.Gln61His (n=1), 3.6% were p.Asp126His (n=1), and 3.6% were p.Lys169Glu (n=1). The p.Asp73= polymorphism was detected in 57.1% of the samples (n=16). KRAS mutation status did not differ significantly between the groups based on the age of onset, sex, tumor location, tumor histology, stage, and family history.

CONCLUSION

KRAS mutations are present in high frequency in this cohort of CRC patients in a tertiary hospital in West Java, Indonesia. However, KRAS mutation status is not associated with the age of onset, sex, tumor location, tumor histology, stage, and family history.

Management of Metastatic Colorectal Cancer (mCRC): Real-World Recommendations

INTRODUCTION

Metastatic CRC is considered as a heterogenous disease. Its management is therefore complex and dynamic. In order the give a ready reference to community oncologists, we developed this real world recommendations.

METHODS

A group of experts with academic background and real world experience in mCRC got together. We reviewed the current literature and the insights gained from our real world experience. Based on the same we put together these recommendations.

RECOMMENDATIONS RESULTS

Molecular testing should be done wherever possible. Most of these patients will be treated with a palliative approach. Doublet chemotherapy is a long-standing standard of care. Triplet therapy may be offered where a more aggressive approach is indicated. Combination with anti -vascular endothelial growth factor antibodies and/or anti EGFR antibodies is also considered standard. In the first-line setting, pembrolizumab can be used for patients with mCRC and microsatellite instability-high or deficient mismatch repair tumours; Left and right sided tumours are distinct entities. Combination of chemotherapy and targeted therapy is used as per individual patient and tumour characteristics.Oligometastatic disease can be approached with potentially curative intent. Cytoreductive surgery plus chemotherapy can be offered to selected patients with peritoneal only metastases. Stereotactic body radiation therapy can be used as local therapy for patients with oligometastatic liver only disease who cannot be taken up for surgery. New strategies include induction-maintenance chemotherapy and perioperative chemotherapy. All drugs/ regimen included as standard of care in the first line can also be used in subsequent lines. Specific targetable driver mutation tumours can be treated accordingly with their complementary biological therapy.

CONCLUSION

Multidisciplinary team management and shared decision making are possible when patient and caregivers choose to become active participants.

Clinicopathological, molecular, and prognostic features of colorectal carcinomas with KRAS c.34G>T (p.G12C) mutation

Evidence indicates that combinations of anti-EGFR antibodies and KRAS p.G12C (c.34G>T) inhibitors can be an effective treatment strategy for advanced colorectal cancer. We hypothesized that KRAS c.34G>T (p.G12C)-mutated colorectal carcinoma might be a distinct tumor subtype. We utilized a prospective cohort incident tumor biobank (including 1347 colorectal carcinomas) and detected KRAS c.34G>T (p.G12C) mutation in 43 cases (3.2%) and other KRAS mutations (in codon 12, 13, 61, or 146) in 467 cases (35%). The CpG island methylator phenotype (CIMP)-low prevalence was similarly higher in KRAS c.34G>T mutants (52%) and other KRAS mutants (49%) than in KRAS-wild-type tumors (31%). KRAS c.34G>T mutants showed higher CIMP-high prevalence (14%) and lower CIMP-negative prevalence (33%) compared with other KRAS mutants (6% and 45%, respectively; p = 0.0036). Similar to other KRAS mutants, KRAS c.34G>T-mutated tumors were associated with cecal location, non-microsatellite instability (MSI)-high status, BRAF wild type, and PIK3CA mutation when compared with KRAS-wild-type tumors. Compared with BRAF-mutated tumors, KRAS c.34G>T mutants showed more frequent LINE-1 hypomethylation, a biomarker for early-onset colorectal carcinoma. KRAS c.34G>T mutants were not associated with other features, including the tumor tissue abundance of Fusobacterium nucleatum (F. animalis), pks+ Escherichia coli, Bifidobacterium, or (enterotoxigenic) Bacteroides fragilis. Among 1122 BRAF-wild-type colorectal carcinomas, compared with KRAS-wild-type tumors, multivariable-adjusted colorectal cancer-specific mortality hazard ratios (95% confidence interval) were 1.82 (1.05-3.17) in KRAS c.34G>T (p.G12C)-mutated tumors (p = 0.035) and 1.57 (1.22-2.02) in other KRAS-mutated tumors (p = 0.0004). Our study provides novel evidence for clinical and tumor characteristics of KRAS c.34G>T (p.G12C)-mutated colorectal carcinoma.

Biomarker-stratified first-line treatment of right-sided metastatic colon cancer with interdisciplinary collaboration in the IVOPAK II trial

Patients with right-sided metastatic colon carcinoma have a significantly worse prognosis than those with left-sided colorectal cancer (CRC), regardless of treatment. The aim of the prospective IVOPAK II study was to implement an interdisciplinary guideline-conform personalized CRC palliative therapy of metastatic colorectal carcinoma and to improve the overall survival (OS) by multidisciplinary approach via secondary metastatic resection. We present the efficacy data of first-line treatment and the benefit of interdisciplinary collaboration of right-sided metastatic colon carcinoma patients: n  = 25. RAS mutation: n  = 20 (80%): received systemic first-line treatment: FOLFIRI plus bevacizumab. All-RAS-wildtype: n  = 5 (20%): received systemic first-line treatment: FOLFIRI plus cetuximab. Last date evaluation: 31 January 2024. Median age: 59.6 years (range 42-71), men/women: 14/11. Eastern Cooperative Oncology Group (ECOG) index: 0/1/2 : 11/10/4. Evaluable for response: n  = 25. Complete response: n  = 0, partial response: n  = 14 (56%), stable disease: n  = 8 (32%), progressive disease: n  = 3 (12%), early tumor shrinkage: n  = 13 (52%), estimates progression-free survival: 13 months (95% CI 8-17 months), estimated OS: 48 months (95% CI 25-71 months), median follow-up: 26 months (1-61 months), no evidence of disease: n  = 4 (16%). A chemotherapy doublette regimen with FOLFIRI plus a biological as first-line treatment shows promising efficacy and secondary metastatic resection after interdisciplinary discussion was associated with a survival benefit in right-sided metastatic colon carcinoma.

WEE1 Inhibitor Adavosertib Exerts Antitumor Effects on Colorectal Cancer, Especially in Cases with p53 Mutations

Inhibition of WEE1, a key regulator of the G2/M checkpoint of the cell cycle, induces apoptosis by initiating mitosis without repairing DNA damage. However, the effects of WEE1 inhibitors on the tumor immune microenvironment in colorectal cancer (CRC) remain unclear. Here, we investigated the association between WEE1 expression and CRC clinicopathological features using surgically resected CRC specimens and assessed the antitumor effects of a WEE1 inhibitor using CRC cell lines and orthotopic transplantation mouse models. WEE1 expression was not correlated with the clinicopathological features of CRC. The WEE1 inhibitor suppressed cell proliferation in a concentration-dependent manner in all CRC cell lines. It also increased the percentage of cells in the G2/M phase and apoptotic cells, especially in cell lines with p53 mutations, but did not alter these cell percentages in most p53 wild-type cell lines. In the orthotopic mouse model of CRC, tumor volume was significantly reduced in the WEE1 inhibitor-treated group compared to that in the control group. RNA sequencing and immunohistochemistry analyses of mouse tumors revealed that treatment with the WEE1 inhibitor activated tumor immunity and suppressed stromal reactions. These results demonstrate the potential antitumor effects of WEE1 inhibitors in CRC, particularly in patients with p53 mutations.

Returning from the afterlife? Sotorasib treatment for advanced KRAS mutant lung cancer: A case report

BACKGROUND

Lung cancer is increasing in incidence worldwide, and targeted therapies are developing at a rapid pace. Furthermore, the KRAS specific gene is strongly associated with non-small cell lung cancer (NSCLC). Adult patients with locally advanced or metastatic NSCLC who have tested positive for the KRAS G12C mutation and have progressed after at least one systemic treatment are treated with sotorasib.

CASE SUMMARY

In this study, we report on an advanced NSCLC with a KRAS G12C mutation. The histological diagnosis indicates stage IVB left lung adenocarcinoma with pelvic and bone metastases, identified as cT4N2bM1c. Using circulating tumor DNA analysis, it was possible to determine the mutation abundance of the KRAS gene exon 2, c.34G>Tp.G12C, which was 32.3%. The patient was advised to take sotorasib as part of their treatment. The imaging data were compared before and after treatment. Furthermore, clinical reassessments and regular serial blood testing were conducted. We found that the patient's clinical symptoms significantly improved after receiving sotorasib medication, and there were no notable side effects, such as liver toxicity, during the treatment.

CONCLUSION

Sotorasib has shown promising clinical efficacy in patients with the KRAS G12c mutation and has no apparent toxic side effects.

KRAS G12C Inhibitors in the Treatment of Metastatic Colorectal Cancer

KRAS mutations contribute substantially to the overall colorectal cancer burden and have long been a focus of drug development efforts. After a lengthy preclinical road, KRAS inhibition via the G12C allele has finally become a therapeutic reality. Unlike in NSCLC, early studies of KRAS inhibitors in CRC struggled to demonstrate single agent activity. Investigation into these tissue-specific treatment differences has led to a deeper understanding of the complexities of MAPK signaling and the diverse adaptive feedback responses to KRAS inhibition. EGFR reactivation has emerged as a principal resistance mechanism to KRAS inhibitor monotherapy. Thus, the field has pivoted to dual EGFR/KRAS blockade with promising efficacy. Despite significant strides in the treatment of KRAS G12C mutated CRC, new challenges are on the horizon. Alternative RTK reactivation and countless acquired molecular resistance mechanisms have shifted the treatment goalpost. This review focuses on the historical and contemporary clinical strategies of targeting KRAS G12C alterations in CRC and highlights future directions to overcome treatment challenges.

Safety and Efficacy of Vicriviroc (MK-7690) in Combination With Pembrolizumab in Patients With Advanced or Metastatic Microsatellite Stable Colorectal Cancer

BACKGROUND

Pembrolizumab, a monoclonal antibody against PD-1, has shown limited efficacy in patients with microsatellite stable or mismatch repair proficient (MSS/pMMR) metastatic colorectal cancer (CRC). We evaluated vicriviroc (small-molecule C-C motif chemokine ligand 5 antagonist) plus pembrolizumab in patients with advanced or metastatic MSS/pMMR CRC.

PATIENTS AND METHODS

This open-label, phase 2 trial (NCT03631407) enrolled adults with histologically confirmed, locally advanced, unresectable or metastatic CRC that was MSS per local assessment. All patients had received previous treatment with standard therapies. Patients were randomized 1:1 to vicriviroc 150 mg orally once daily plus pembrolizumab 200 mg intravenously every 3 weeks or vicriviroc 250 mg orally once daily plus pembrolizumab 200 mg intravenously every 3 weeks for up to 35 cycles (2 years). Primary endpoints were the objective response rate (ORR) as assessed by the investigator per RECIST v1.1, dose-limiting toxicities (DLTs), adverse events (AEs), and discontinuations due to AEs.

RESULTS

Forty patients were enrolled and treated. ORR was 5% (95% CI, 0.1%-24.9%) in both treatment groups. There were no complete responses; 1 patient in each treatment group experienced a partial response. No patient in the vicriviroc 150 mg plus pembrolizumab group experienced a DLT. Two patients in the vicriviroc 250 mg plus pembrolizumab group experienced DLTs (1 grade 4 encephalopathy and 1 grade 4 pneumonitis).

CONCLUSION

The combination of vicriviroc at doses of 150 or 250 mg plus pembrolizumab 200 mg showed limited antitumor activity in patients with advanced or metastatic MSS/pMMR CRC. Toxicity with the combination was manageable.

Impact of primary tumor sidedness and sex on prognosis and anti-epidermal growth factor receptor antibody efficacy in BRAF-mutant metastatic colorectal cancer: a pooled analysis of AIO studies FIRE-1, CIOX, FIRE-3, XELAVIRI, and VOLFI

BACKGROUND

Primary tumor (PT) sidedness is an established prognostic marker in metastatic colorectal cancer (mCRC) and has a predictive impact on the efficacy of anti-epidermal growth factor receptor (anti-EGFR) antibody [monoclonal antibody (mAb)] in patients with RAS wild-type mCRC. This investigation focuses on patients with BRAFV600E-mutated (BRAFmt) mCRC and examines the efficacy of anti-EGFR mAbs in relation to primary tumor sidedness (PTS).

PATIENT AND METHODS

This pooled analysis was carried out using individual patient data from five randomized studies in the first-line setting of mCRC. The population of interest was limited to patients with BRAFmt mCRC and known PTS. For analysis, treatment was stratified into two groups: those treated with anti-EGFR mAbs and those without. Dichotomous variables, such as overall response rate and objective response rate (ORR), were compared using chi-square or Fisher's exact test. Time-to-event endpoints [progression-free survival (PFS) and overall survival (OS)] were analyzed using the Kaplan-Meier method, log-rank test, and Cox regression. An interaction test was carried out via Cox regression.

RESULTS

A total of 102 patients with BRAFmt mCRC were identified. The type of targeted therapy (anti-EGFR-based versus non-anti-EGFR) did not significantly impact the outcome. However, in patients with left-sided primary tumors, anti-EGFR mAb-based treatment, compared with non-anti-EGFR, was associated with a higher ORR (58% versus 34%; P < 0.01), trended toward improved PFS [hazard ratio (HR) 0.62; 95% confidence interval (CI) 0.34-1.13; P = 0.12], and demonstrated prolonged OS (HR 0.38; 95% CI 0.20-0.72; P < 0.01). In patients with right-sided primary tumors, anti-EGFR-based therapy had no effect on ORR (33% versus 36%; P > 0.99), induced inferior PFS (HR 1.97; 95% CI 1.12-3.47; P = 0.02), and trended toward a worse OS (HR 1.76; 95% CI 0.99-3.13; P = 0.05).

CONCLUSION

This analysis suggests that PTS has predictive value for the efficacy of anti-EGFR mAb in the first-line treatment of BRAFmt mCRC.

Regorafenib plus FOLFIRINOX as first-line treatment for patients with RAS-mutant metastatic colorectal cancer (FOLFIRINOX-R trial): a dose-escalation study

PURPOSE

The combination of bevacizumab and FOLFIRINOX is used in patients with RAS-mutant metastatic colorectal cancer (RASm-mCRC). Regorafenib, an oral multi-tyrosine kinase inhibitor, has antiangiogenic properties, cytostatic effects and also true cytotoxic effects, unlike bevacizumab. The aim of this study was to determine the maximum tolerated dose (MTD) and the recommended phase 2 dose (RP2D) of the regorafenib-FOLFIRINOX combination in patients with RASm-mCRC.

METHODS

The FOLFIRINOX-R trial was a phase 1/2 study where the dose-escalation part (3 + 3 design with three dose levels, DLs) was completed before its early termination. FOLFIRINOX (14-day cycle) included oxaliplatin (standard dose), folinic acid, fluorouracil and irinotecan (150 or 180 mg/m²). Regorafenib (120 or 160 mg daily) was given from day 4 to day 10 of each cycle. Dose-limiting toxicity (DLT) was studied in the first three cycles. Eligibility criteria included ECOG performance status ≤ 1 and not previously treated RASm-mCRC.

RESULTS

Thirteen patients (median age: 65 years; min-max: 40-76) were enrolled. DLT could not be evaluated in one patient (DL3) due to poor observance. The median treatment duration and median follow-up were 6.2 (min-max: 2.3-10) and 13.4 (min-max: 3.8-18.0) months, respectively. Dose was modified in 12/13 (92%) patients. One grade 3 hypokalemia occurred at DL2. MTD was not reached at DL3. Grade 3 diarrhea was recorded in 7/13 patients (13 events) equally distributed in all DLs.

CONCLUSION

The RP2D for this regorafenib-FFX combination could not be determined due to a high prevalence of grade 3 diarrhea related to treatment as advised by our Independent Data Monitoring Committee.

TRIAL REGISTRATION NUMBERS

ClinicalTrials.gov : NCT03828799.

Honokiol enhances the sensitivity of cetuximab in KRASG13D mutant colorectal cancer through destroying SNX3-retromer complex

Rationale : the proto-oncogene KRAS is frequently mutated in colorectal cancer (CRC), leading to inherent resistance against monoclonal antibodies targeting the epidermal growth factor receptor (EGFR), such as cetuximab. Therefore, addressing the primary resistance and expanding the indications for target therapy have become critical challenges. Methods : the screening of a natural product library against KRAS mutant CRC cells was conducted, leading to the discovery of a small molecule compound that sensitive to the KRASG13D mutation site. The anti-tumor activity of this small molecule compound in combination with cetuximab was evaluated using the KRASG13D mutant CRC models both in vivo and in vitro. This evaluation includes an examination of its effects on cell proliferation, viability, apoptosis, cell cycle progression, and tumor growth. Furthermore, RNA sequencing, western blot analysis, immunofluorescence, real-time quantitative PCR, and pull-down assays were employed to explore the molecular mechanisms underlying the synergistic anti-tumor effect of this small molecule compound in combination with cetuximab. Results : our study screened 882 compounds in KRAS mutant CRC cells and identified honokiol, a small molecule compound that exhibits specific sensitivity to KRASG13D mutant CRC cells. Furthermore, we revealed that the synergistic augmentation of cetuximab's sensitivity in vivo and in vitro models of KRASG13D mutant CRC in combination with honokiol. Mechanistically, honokiol suppresses SNX3-retromer mediated trafficking, thereby impeding lysosomal proteolytic capacity and inhibiting autophagy and macropinocytosis fluxes. Moreover, honokiol inhibits the conversion of RAS GDP to RAS GTP, heightening the susceptibility of KRASG13D CRC mutant cells to cetuximab. Conclusions : honokiol enhances the sensitivity of cetuximab by destroying SNX3 retromer in KRASG13D mutant CRC preclinical model. These findings present a promising strategy for expanding the indications of target therapy in KRAS mutant colorectal cancer patients.

Efficacy-effectiveness analysis on survival in a population-based real-world study of BRAF-mutated metastatic colorectal cancer patients treated with encorafenib-cetuximab

BACKGROUND

Encorafenib-cetuximab has been approved for pretreated BRAFV600E-mutated metastatic colorectal cancer (mCRC) patients based on efficacy demonstrated in the randomized phase III BEACON trial. The aim of this real-world effectiveness study is to improve knowledge on the generalizability of trial results.

METHODS

This population-based real-world study includes all mCRC patients in the Netherlands treated with encorafenib-cetuximab since approval. Individual patient data and pathology reports were collected. Overall survival (OS) was compared to BEACON and subgroup analyses were conducted for patients who would have been eligible and ineligible for BEACON.

RESULTS

166 patients were included with a median follow-up time of 14.5 months. Median OS was 6.7 months (95% CI:6.0-8.3) and differed from BEACON (9.3 months; 95% CI:8.0-11.3, p-value 0.002). Thirty-six percent of real-world patients would have been ineligible for the BEACON trial. Trial ineligible subgroups with symptomatic brain metastases and WHO performance status ≥2 had the poorest median OS of 5.0 months (95% CI:4.0-NR) and 3.9 months (95% CI:2.4-NR).

CONCLUSION

This real-world cohort of mCRC patients treated with encorafenib-cetuximab showed a clinically relevant efficacy-effectiveness gap for OS. The chance of survival benefit from encorafenib-cetuximab in patients with brain metastases and/or WHO performance status ≥2 is negligible as neither efficacy nor effectiveness has been demonstrated.

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.

Genetic Profiling and Survival Outcomes in Romanian Colorectal Cancer Patients

BACKGROUND

The increasing incidence of colorectal cancer is one of the most frequently addressed medical topics worldwide. It represents the third most commonly diagnosed cancer in both men and women globally, with significant implications for public health. Mortality for this type of malignancy remains high, second only to lung cancer. Given their clinical relevance, the identification and understanding of KRAS and BRAF mutations have become crucial components of personalized medicine approaches in colorectal cancer. Hence, our desire is to carry out a research that analyzes the impact of these mutations in terms of survival and mortality on patients diagnosed with colorectal cancer.

METHODS

We conducted a retrospective study spanning from 2018 to 2022, which involved 118 patients diagnosed with colorectal cancer. The patients were selected from the databases of the Oradea County Emergency Clinical Hospital and Pelican Oradea Hospital. Genetic testing was performed at the "Resident Laboratory" clinic. Subsequently, patients were divided into two groups of equal size based on the presence or absence of mutations.

RESULTS

The survival rate one year after the diagnosis of colorectal cancer is 84.74% (N=50/59) for the mutant group versus 67.96% (N=40/59) for the wild-type group. The survival rate at five years from the diagnosis of colorectal cancer is 25.93% (N=15/59) for patients with wild-type tumors compared to 33.54% (N=20/59) for patients with tumors with mutant status (p=0.483, HR=1.153, CI 95% 0.7661-1.735). The five-year survival rate, depending on the mutation present, highlights the fact that the average overall survival for those with the KRAS mutation is 38.6 months (CI 95% 35.22-41.97) and for those with the BRAF mutation is 8.3 months (CI 95% 5.42-11.17) (p=0.039). The mortality rate for mutant KRAS is 44.89% (N=22/50), while for those with mutant BRAF, it is 100% (N=6/6).

CONCLUSIONS

We observed no statistically significant difference in overall survival rate and disease-free interval between the two studied groups, but the overall survival was better for those with mutations present (38.64 months versus 31.07 months for wild-type tumors). The mortality rate is higher among tumors with wild-type status (p=0.005), in the first year after the diagnosis of colorectal cancer. The BRAF mutation confers a much worse prognosis than the KRAS mutation, from both the survival analysis and the mortality rate.

Tumor biomarkers for diagnosis, prognosis and targeted therapy

Tumor biomarkers, the substances which are produced by tumors or the body's responses to tumors during tumorigenesis and progression, have been demonstrated to possess critical and encouraging value in screening and early diagnosis, prognosis prediction, recurrence detection, and therapeutic efficacy monitoring of cancers. Over the past decades, continuous progress has been made in exploring and discovering novel, sensitive, specific, and accurate tumor biomarkers, which has significantly promoted personalized medicine and improved the outcomes of cancer patients, especially advances in molecular biology technologies developed for the detection of tumor biomarkers. Herein, we summarize the discovery and development of tumor biomarkers, including the history of tumor biomarkers, the conventional and innovative technologies used for biomarker discovery and detection, the classification of tumor biomarkers based on tissue origins, and the application of tumor biomarkers in clinical cancer management. In particular, we highlight the recent advancements in biomarker-based anticancer-targeted therapies which are emerging as breakthroughs and promising cancer therapeutic strategies. We also discuss limitations and challenges that need to be addressed and provide insights and perspectives to turn challenges into opportunities in this field. Collectively, the discovery and application of multiple tumor biomarkers emphasized in this review may provide guidance on improved precision medicine, broaden horizons in future research directions, and expedite the clinical classification of cancer patients according to their molecular biomarkers rather than organs of origin.

Onvansertib in Combination with FOLFIRI and Bevacizumab in Second-Line Treatment of KRAS-Mutant Metastatic Colorectal Cancer: A Phase Ib Clinical Study

PURPOSE

Onvansertib is a highly specific inhibitor of polo-like kinase 1 (PLK1), with demonstrated safety in solid tumors. We evaluated, preclinically and clinically, the potential of onvansertib in combination with chemotherapy as a therapeutic option for KRAS-mutant colorectal cancer.

PATIENTS AND METHODS

Preclinical activity of onvansertib was assessed (i) in vitro in KRAS wild-type and -mutant isogenic colorectal cancer cells and (ii) in vivo, in combination with irinotecan, in a KRAS-mutant xenograft model. Clinically, a phase Ib trial was conducted to investigate onvansertib at doses 12, 15, and 18 mg/m2 (days 1-5 and 14-19 of a 28-day cycle) in combination with FOLFIRI/bevacizumab (days 1 and 15) in patients with KRAS-mutant metastatic colorectal cancer who had prior oxaliplatin exposure. Safety, efficacy, and changes in circulating tumor DNA (ctDNA) were assessed.

RESULTS

In preclinical models, onvansertib displayed superior activity in KRAS-mutant than wild-type isogenic colorectal cancer cells and demonstrated potent antitumor activity in combination with irinotecan in vivo. Eighteen patients enrolled in the phase Ib study. Onvansertib recommended phase II dose was established at 15 mg/m2. Grade 3 and 4 adverse events (AE) represented 15% of all treatment-related AEs, with neutropenia being the most common. Partial responses were observed in 44% of patients, with a median duration of response of 9.5 months. Early ctDNA dynamics were predictive of treatment efficacy.

CONCLUSIONS

Onvansertib combined with FOLIFRI/bevacizumab exhibited manageable safety and promising efficacy in second-line treatment of patients with KRAS-mutant metastatic colorectal cancer. Further exploration of this combination therapy is ongoing. See related commentary by Stebbing and Bullock, p. 2005.

Unraveling the Interplay of KRAS, NRAS, BRAF, and Micro-Satellite Instability in Non-Metastatic Colon Cancer: A Systematic Review

Microsatellite Instability (MSI-H) occurs in approximately 15% of non-metastatic colon cancers, influencing patient outcomes positively compared to microsatellite stable (MSS) cancers. This systematic review focuses on the prognostic significance of KRAS, NRAS, and BRAF mutations within MSI-H colon cancer. Through comprehensive searches in databases like MEDLINE, EMBASE, and others until 1 January 2024, we selected 8 pertinent studies from an initial pool of 1918. These studies, encompassing nine trials and five observational studies involving 13,273 patients, provided insights into disease-free survival (DFS), survival after recurrence, and overall survival. The pooled data suggest that while KRAS and BRAF mutations typically predict poorer outcomes in MSS colorectal cancer, their impact is less pronounced in MSI contexts, with implications varying across different stages of cancer and treatment responses. In particular, adverse effects of these mutations manifest significantly upon recurrence rather than affecting immediate DFS. Our findings confirm the complex interplay between genetic mutations and MSI status, emphasizing the nuanced role of MSI in modifying the prognostic implications of KRAS, NRAS, and BRAF mutations in colon cancer. This review underscores the importance of considering MSI alongside mutational status in the clinical decision-making process, aiming to tailor therapeutic strategies more effectively for colon cancer patients.

The histological and molecular characteristics of early-onset colorectal cancer: a systematic review and meta-analysis

Background

Early-onset colorectal cancer (CRC), defined as diagnosis before age 50, has increased in recent decades. Although more often diagnosed at advanced stage, associations with other histological and molecular markers that impact prognosis and treatment remain to be clarified. We conducted a systematic review and meta-analysis concerning the prevalence of prognostic and predictive tumor markers for early- vs. late-onset CRC, including oncogene mutations, microsatellite instability (MSI), and emerging markers including immune cells and the consensus molecular subtypes.

Methods

We systematically searched PubMed for original research articles published between April 2013-January 2024. Included studies compared the prevalence of tumor markers in early- vs. late-onset CRC. A meta-analysis was completed and summary odds ratios (ORs) with 95% confidence intervals (CIs) were obtained from a random effects model via inverse variance weighting. A sensitivity analysis was completed to restrict the meta-analysis to studies that excluded individuals with Lynch syndrome, a hereditary condition that influences the distribution of tumor markers for early-onset CRC.

Results

In total, 149 articles were identified. Tumors from early-onset CRC are less likely to include mutations in KRAS (OR, 95% CI: 0.91, 0.85-0.98), BRAF (0.63, 0.51-0.78), APC (0.70, 0.58-0.84), and NRAS (0.88, 0.78-1.00) but more likely to include mutations in PTEN (1.68, 1.04-2.73) and TP53 (1.34, 1.24-1.45). After limiting to studies that excluded Lynch syndrome, the associations between early-onset CRC and BRAF (0.77, 0.64-0.92) and APC mutation (0.81, 0.67-0.97) were attenuated, while an inverse association with PIK3CA mutation was also observed (0.88, 0.78-0.99). Early-onset tumors are less likely to develop along the CpG Island Methylator Phenotype pathway (0.24, 0.10-0.57), but more likely to possess adverse histological features including high tumor grade (1.20, 1.15-1.25), and mucinous (1.22, 1.16-1.27) or signet ring histology (2.32, 2.08-2.57). A positive association with MSI status (1.31, 1.11-1.56) was also identified. Associations with immune markers and the consensus molecular subtypes are inconsistent.

Discussion

A lower prevalence of mutations in KRAS and BRAF is consistent with extended survival and superior response to targeted therapies for metastatic disease. Conversely, early-onset CRC is associated with aggressive histological subtypes and TP53 and PTEN mutations, which may serve as therapeutic targets.

KMT2A Mutations and High Prevalence of dMMR-associated Mutational Signatures as Prognostic Indicators in Metastatic Colorectal Cancer

The conventional treatment strategies for patients with metastatic colorectal cancer (mCRC) are predominantly guided by the status of RAS and BRAF mutations. Although patients may exhibit analogous pathological characteristics and undergo similar treatment regimens, notable disparities in their prognostic outcomes can be observed. Therefore, tissue and plasma samples from 40 mCRC patients underwent next-generation sequencing targeting 425 cancer-relevant genes. Genomic variations and canonical oncogenic pathways were investigated for their prognostic effects in association with progression-free survival (PFS) of these patients. We found that patients with BRCA2 and KMT2A mutations exhibited worse prognostic outcomes after chemotherapy-based treatment (univariate, P < 0.01). Further pathway analysis indicated that alterations in the homologous recombination pathway and in the KMT2A signaling network were also significantly associated with shortened PFS (univariate, P < 0.01). Additionally, mutation signature analysis showed that patients with higher proportions of defective mismatch repair (dMMR)-related mutational signatures. Had a worse prognosis (univariate, P = 0.02). KMT2A mutations (hazard ratio [HR], 4.47; 95% confidence interval [CI], 1-19.93; P =0.050) and dMMR signature proportions (HR, 3.57; 95% CI, 1.42-8.96; P = 0.007) remained independently associated with PFS after multivariate analysis and the results were further externally validated. These findings may enhance our understanding of this disease and may potentially facilitate the optimization of its treatment approaches.

Prognostic value of specific KRAS mutations in patients with colorectal peritoneal metastases

BACKGROUND

There is little evidence on KRAS mutational profiles in colorectal cancer (CRC) peritoneal metastases (PM). This study aims to determine the prevalence of specific KRAS mutations and their prognostic value in a homogeneous cohort of patients with isolated CRC PM treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

MATERIALS AND METHODS

Data were collected from 13 Italian centers, gathered in a collaborative group of the Italian Society of Surgical Oncology. KRAS mutation subtypes have been correlated with clinical and pathological characteristics and survival [overall survival (OS), local (peritoneal) disease-free survival (LDFS) and disease-free survival (DFS)].

RESULTS

KRAS mutations occurred in 172 patients (47.5%) out of the 362 analyzed. Two different prognostic groups of KRAS mutation subtypes were identified: KRASMUT1 (G12R, G13A, G13C, G13V, Q61H, K117N, A146V), median OS > 120 months and KRASMUT2 (G12A, G12C, G12D, G12S, G12V, G13D, A59E, A59V, A146T), OS: 31.2 months. KRASMUT2 mutations mainly occurred in the P-loop region (P < 0.001) with decreased guanosine triphosphate (GTP) hydrolysis activity (P < 0.001) and were more frequently related to size (P < 0.001) and polarity change (P < 0.001) of the substituted amino acid (AA). When KRASMUT1 and KRASMUT2 were combined with other known prognostic factors (peritoneal cancer index, completeness of cytoreduction score, grading, signet ring cell, N status) in multivariate analysis, KRASMUT1 showed a similar survival rate to KRASWT patients, whereas KRASMUT2 was independently associated with poorer prognosis (hazard ratios: OS 2.1, P < 0.001; DFS 1.9, P < 0.001; LDFS 2.5, P < 0.0001).

CONCLUSIONS

In patients with CRC PM, different KRAS mutation subgroups can be determined according to specific codon substitution, with some mutations (KRASMUT1) that could have a similar prognosis to wild-type patients. These findings should be further investigated in larger series.

Dynamic nature of BRAF or KRAS p.G12C mutations in second-line therapy for advanced colorectal cancer patients: do early and late effects exist?

INTRODUCTION

The mitogen-activated protein kinase (MAPK) signalling network aberrations in metastatic colorectal cancer (mCRC) generate intrinsic dynamic effects and temporal variations that are crucial but often overlooked in clinical trial populations. Here, we investigate the time-varying impact of MAPK pathway mutation genotype on each treatment line's contribution to the overall clinical course.

METHODS

The PROMETEO study focused on mCRC patients undergoing second-line treatment at 20 hospitals. We evaluated genotypes and employed flexible models to analyse the dynamic effect of each mutation.

RESULTS

We examined data derived from 1160 patients. The effects of KRAS G12C or G12V, and BRAF V600E are clearly time-varying, with unexpected consequences such as the deleterious effect of BRAF V600E vs other genotypes dissipating over time when subjects receive antiangiogenics, or KRAS G12V and G12C showing increasing aggressiveness over time. Thus, contrary to expectations, the 12-month survival rate from the second line for those who survived >6 months was 49.9% (95% CI, 32.7-67.3) for KRAS G12C and 59% (95% CI, 38.5-80.6) for BRAF V600E.

CONCLUSIONS

The dynamic perspective is essential for understanding the behaviour of tumours with specific genotypes, especially from the second line onward. This may be relevant in patient monitoring and treatment decision-making, particularly in cases with distinct mutations.

Impact of KRASG12 mutations on survival with trifluridine/tipiracil plus bevacizumab in patients with refractory metastatic colorectal cancer: post hoc analysis of the phase III SUNLIGHT trial

BACKGROUND

In metastatic colorectal cancer (mCRC), KRAS mutations are often associated with poorer survival; however, the prognostic impact of specific point mutations is unclear. In the phase III SUNLIGHT trial, trifluridine/tipiracil (FTD/TPI) plus bevacizumab significantly improved overall survival (OS) versus FTD/TPI alone. We assessed the impact of KRASG12 mutational status on OS in SUNLIGHT.

PATIENTS AND METHODS

In the global, open-label, randomized, phase III SUNLIGHT trial, adults with mCRC who had received no more than two prior chemotherapy regimens were randomized 1 : 1 to receive FTD/TPI alone or FTD/TPI plus bevacizumab. In this post hoc analysis, OS was assessed according to the presence or absence of a KRASG12 mutation in the overall population and in patients with RAS-mutated tumors.

RESULTS

Overall, 450 patients were analyzed, including 302 patients in the RAS mutation subgroup (214 with a KRASG12 mutation and 88 with a non-KRASG12RAS mutation). In the overall population, similar OS outcomes were observed in patients with and without a KRASG12 mutation [median 8.3 and 9.2 months, respectively; hazard ratio (HR) 1.09, 95% confidence interval (CI) 0.87-1.4]. Similar OS outcomes were also observed in the subgroup analysis of patients with a KRASG12 mutation versus those with a non-KRASG12RAS mutation (HR 1.03, 95% CI 0.76-1.4). FTD/TPI plus bevacizumab improved OS compared with FTD/TPI alone irrespective of KRASG12 mutational status. Among patients with a KRASG12 mutation, the median OS was 9.4 months with FTD/TPI plus bevacizumab versus 7.2 months with FTD/TPI alone (HR 0.67, 95% CI 0.48-0.93), and in patients without a KRASG12 mutation, the median OS was 11.3 versus 7.1 months, respectively (HR 0.59, 95% CI 0.43-0.81).

CONCLUSIONS

The presence of a KRASG12 mutation had no detrimental effect on OS among patients treated in SUNLIGHT. The benefit of FTD/TPI plus bevacizumab over FTD/TPI alone was confirmed independently of KRASG12 status.

Clinical genomic profiling of malignant giant cell tumor of bone: A retrospective analysis using a real‑world database

Malignant giant cell tumor of bone (GCTB) is identified by the presence of multinucleated giant cells, with an aggressive behavior and a high risk of metastasis, which has not been genetically characterized in detail. H3 histone family member 3A (H3F3A) gene mutations are highly recurrent and specific in GCTB. The present study analyzed the clinical information and genomic sequencing data of eight cases of malignant GCTB (out of 384 bone sarcoma samples) using an anonymized genomic database. There were 5 males and 3 females among the cases, with a median age of 33 years at the time of the initial diagnosis. H3F3A G34W and G34L mutations were detected in 3 patients and 1 patient, respectively. In 75% of cases without H3F3A mutation, mitogen-activated protein kinase (MAPK) signaling pathway gene alterations were found (KRAS single nucleotide variant, KRAS amplification, nuclear respiratory factor 1-BRAF fusion). Moreover, the collagen type I alpha 2 chain-ALK fusion was detected in remaining one case. The most frequent gene alterations were related to cell cycle regulators, including TP53, RB1, cyclin-dependent kinase inhibitor 2A/B and cyclin E1 (75%, 6 of 8 cases). On the whole, the present study discovered recurrent MAPK signaling gene alterations or other gene alterations in cases of malignant GCTB. Of note, two fusion genes should be carefully validated following the pathology re-review by sarcoma pathologists. These two fusion genes may be detected in resembling tumors, which contain giant cells, apart from malignant GCTB. The real-world data used herein provide a unique perspective on genomic alterations in clinicopathologically diagnosed malignant GCTB.

Contemporary Surgical Management of Colorectal Liver Metastases

Colorectal cancer is the third most common cancer in the United States and the second most common cause of cancer-related death. Approximately 20-30% of patients will develop hepatic metastasis in the form of synchronous or metachronous disease. The treatment of colorectal liver metastasis (CRLM) has evolved into a multidisciplinary approach, with chemotherapy and a variety of locoregional treatments, such as ablation and portal vein embolization, playing a crucial role. However, resection remains a core tenet of management, serving as the gold standard for a curative-intent therapy. As such, the input of a dedicated hepatobiliary surgeon is paramount for appropriate patient selection and choice of surgical approach, as significant advances in the field have made management decisions extremely nuanced and complex. We herein aim to review the contemporary surgical management of colorectal liver metastasis with respect to both perioperative and operative considerations.

Unveiling the role of KRAS in tumor immune microenvironment

Kirsten rats sarcoma viral oncogene (KRAS), the first discovered human oncogene, has long been recognized as "undruggable". KRAS mutations frequently occur in multiple human cancers including non-small cell lung cancer(NSCLC), colorectal cancer(CRC) and pancreatic ductal adenocarcinoma(PDAC), functioning as a "molecule switch" determining the activation of various oncogenic signaling pathways. Except for its intrinsic pro-tumorigenic role, KRAS alteration also exhibits an unique immune signature characterized by elevated PD-L1 level and high tumor mutational burden(TMB). KRAS mutation shape an immune suppressive microenvironment by impeding effective T cells infiltration and recruiting suppressive immune cells including myeloid-derived suppressor cells(MDSCs), regulatory T cells(Tregs), cancer associated fibroblasts(CAFs). In immune checkpoint inhibitor(ICI) era, NSCLC patients with mutated KRAS tend to be more responsive to ICI than patients with intact KRAS. The hallmark for KRAS mutation is the existence of multiple kinds of co-mutations. Different types of co-alterations have distinct tumor microenvironment(TME) signatures and responses to ICI. TP53 co-mutation possess a "hot" TME and achieve higher response to immunotherapy while other loss of function mutation correlated with a "colder" TME and a poor outcome to ICI-based therapy. The groundbreaking discovery of KRAS G12C inhibitors significantly improved outcomes for this KRAS subtype even though efficacy was limited to NSCLC patients. KRAS G12C inhibitors also restore the suppressive TME, creating an opportunity for combinations with ICI. However, an inevitable challenge to KRAS inhibitors is drug resistance. Promising combination strategies such as combination with SHP2 is an approach deserve further exploration because of their immune modulatory effect.

Engineered a dual-targeting HA-TPP/A nanoparticle for combination therapy against KRAS-TP53 co-mutation in gastrointestinal cancers

KRAS-TP53 co-mutation is strongly associated with poor prognosis and high malignancy in gastrointestinal cancers. Therefore, a novel approach to oncotherapy may lie in combination therapy targeting both KRAS and TP53. Herein, we present a novel self-assembled nanoparticle (HA-TPP/A) that are functionalized nano-carrier hyaluronic acid (HA)-TPP conjugate (HA-TPP) to degrade mutant p53 proteins (mutp53) and co-deliver AMG510 for treating KRAS-TP53 co-alteration of gastrointestinal cancers by inhibiting the mutant KRAS and mutp53 signaling pathways. The HA-TPP/A nanoparticles led to ubiquitination-dependent proteasomal degradation of mutp53 by targeting damage to mitochondria. Furthermore, these nanoparticles abrogated the gain-of-function (GOF) phenotypes of mutp53 and increased sensitivity to AMG510-induced cell killing, thereby reducing cell proliferation and migration in gastrointestinal cancer with KRAS-TP53 co-mutation. The co-loaded HA-TPP/A nanoparticles demonstrated remarkable therapeutic efficacy in a tumor-bearing mouse model, particularly in KRAS-TP53 double mutant expressing cancer cells, compared with single drug and combined free drug groups. Notably, HA-TPP/A is the first reported nanoparticle with an ability to co-target KRAS-TP53, providing a promising approach for therapy in highly malignant gastrointestinal tumors and potentially expanding clinical indications for AMG510 targeted therapies in gastrointestinal tumors.

Racial disparities in colorectal cancer clinicopathological and molecular tumor characteristics: a systematic review

PURPOSE

African Americans have the highest colorectal cancer (CRC) mortality of all racial groups in the USA, which may relate to differences in healthcare access or advanced stage at diagnosis. Recent evidence indicates that differences in tumor characteristics may also underlie disparities in mortality. To highlight recent findings and areas for investigation, we completed the first systematic review of racial disparities in CRC tumor prognostic markers, including clinicopathological markers, microsatellite instability (MSI), oncogene mutations, and novel markers, including cancer stem cells and immune markers.

METHODS

Relevant studies were identified via PubMed, limited to original research published within the last 10 years. Ninety-six articles were identified that compared the prevalence of mortality-related CRC tumor characteristics in African Americans (or other African ancestry populations) to White cases.

RESULTS

Tumors from African ancestry cases are approximately 10% more likely to contain mutations in KRAS, which confer elevated mortality and resistance to epidermal growth factor receptor inhibition. Conversely, African Americans have approximately 50% lower odds for BRAF-mutant tumors, which occur less frequently but have similar effects on mortality and therapeutic resistance. There is less consistent evidence supporting disparities in mutations for other oncogenes, including PIK3CA, TP53, APC, NRAS, HER2, and PTEN, although higher rates of PIK3CA mutations and lower prevalence of MSI status for African ancestry cases are supported by recent evidence. Although emerging evidence suggests that immune markers reflecting anti-tumor immunity in the tumor microenvironment may be lower for African American cases, there is insufficient evidence to evaluate disparities in other novel markers, cancer stem cells, microRNAs, and the consensus molecular subtypes.

CONCLUSION

Higher rates of KRAS-mutant tumors in in African Americans may contribute to disparities in CRC mortality. Additional work is required to understand whether emerging markers, including immune cells, underlie the elevated CRC mortality observed for African Americans.