The efficacy of immunotherapy in non-small cell lung cancer with KRAS mutation: a systematic review and meta-analysis.

PURPOSE: The KRAS mutation is highly prevalent in NSCLC and is associated with poor efficacy of immunotherapy. Nevertheless, the impact of KRAS mutation, mutation subtypes, and co-mutations on the effectiveness of immunotherapy remains uncertain. This study aimed to assess the influence of the KRAS mutation on the effectiveness of immunotherapy in NSCLC, specifically examining different subtypes of KRAS mutations and co-mutations. METHODS: We performed an extensive search of multiple databases, covering the period from January 1, 2000, to December 5, 2023. A total of 24 articles met our inclusion criteria and were included in this study. A comparative analysis assessed the influence of different subgroups, including KRAS mutation, KRAS wild-type, KRAS G12C mutation, KRAS G12D mutation, and KRAS with co-mutations in NSCLC with immunotherapy. The study outcomes include HR, with corresponding 95% CI and P-values for OS and PFS using Review Manager 5.4 software for the meta-analysis. RESULT: The KRAS mutation appears to have a more beneficial impact on OS (HR 0.54 [95% CI: 0.41-0.71]; P < 0.00001) and PFS (HR 0.63 [95% CI: 0.53-0.76]; P < 0.00001) in NSCLC patients receiving immunotherapy compared to those without immunotherapy. The presence of KRASG12C mutation has been found to have a positive impact on PFS (HR 0.39 [95% CI: 0.25-0.62]; P < 0.0001) in NSCLC patients who undergo immunotherapy, compared to those who did not receive immunotherapy. KRAS non-G12D mutation is considerably associated with longer OS (HR 1.52 [95% CI: 1.10-2.10]; P = 0.01). The clinical benefit in OS between patients without STK11 co-mutation and those who have KRAS mutation with STK11 is significant (HR 1.46 [95% CI: 1.10-1.93]; P = 0.008). Comparing the impact of OS patients without KEAP1/NFE2L2 mutation to those with KRAS and KEAP1/NFE2L2 co-mutations showed a significant impact (HR 1.89 [95% CI: 1.33-2.68]; P = 0.0004). CONCLUSION: The KRAS mutation and KRAS G12C mutation confer benefits that impact OS and PFS in NSCLC patients treated with immunotherapy. However, the KRAS G12D mutation negatively impacts OS compared to the KRAS non-G12D mutation. Furthermore, KRAS co-mutations involving STK11 and KEAP1/NFE2L2 are associated with a negative impact on the efficacy of immunotherapy in NSCLC patients.

Macropinocytosis-targeted peptide-docetaxel conjugate for bystander pancreatic cancer treatment.

Oncogenic Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations are highly prevalent in pancreatic ductal adenocarcinoma (PDAC) and have garnered attention as potential target for targeted therapies, such as KRAS inhibitors. However, the limited therapeutic efficacy of KRAS allele-specific inhibitors necessitate an efficient pan-KRAS cancer cell killing strategy. Here, we have examined enhanced macropinocytosis pathway in KRAS mutant cancer cells and report improved intracellular delivery of albumin-based therapeutics. We further established an albumin-binding peptide-docetaxel conjugate platform (MPD3), which has a caspase-3 cleavable feature, for macropinocytosis-targeted bystander payload delivery and realization of bystander killing of pan-KRAS cancer cells, complemented with caspase-3 mediated activation of MPD3 to bolster tumoral accumulation of cytotoxic payloads. Utilization of in vitro co-culture system of pan-KRAS cancer cells and pharmacodynamic marker staining revealed potent bystander killing effects of MPD3, highlighting MPD3 as an efficient delivery platform against pan-KRAS cancer. Moreover, MPD3 elicited robust anti-tumor activities in both local and liver metastatic PDAC tumor models in mice. Overall, this work establishes a paradigm for developing translational pan-KRAS cancer treatment and broadens the applicability of albumin binding peptide-drug conjugate against albumin-metabolism enriched cancers.

Endosomal Trafficking Bypassed by the RAB5B-CD109 Interplay Promotes Axonogenesis in KRAS-Mutant Pancreatic Cancer.

Perineural invasion (PNI) represents a unique biological feature associated with poor prognosis in pancreatic ductal adenocarcinoma (PDAC), especially in the presence of KRAS mutations. Extracellular vesicle (EV)-packaged circular RNAs (circRNAs) function as essential mediators of tumor microenvironment communication, triggering PDAC cell invasion and distant metastasis. However, the regulatory mechanisms of EV-packaged circRNAs in the PNI of KRAS-mutant PDAC have not yet been elucidated. Herein, a KRASG12D mutation-responsive EV-packaged circRNA, circPNIT, which positively correlated with PNI in PDAC patients is identified. Functionally, KRASG12D PDAC-derived EV-packaged circPNIT promoted axonogenesis and PNI both in vitro and in vivo. Mechanistically, the circPNIT-mediated Rab5B-CD109 interplay bypassed traditional endosomal trafficking to anchor Rab5B to the lipid rafts of multivesicular bodies and packaged circPNIT into CD109+ EVs. Subsequently, CD109+ EVs delivered circPNIT to neurons by binding to TRPV1 and facilitating DSCAML1 transcription-induced axonogenesis, which in turn enhanced the PNI by activating the GFRα1/RET pathway. Importantly, circPNIT-loaded CD109+ EVs are established to dramatically promote PNI in a KRASG12D/+ Trp53R172H/+ Pdx-1-Cre mouse model. Collectively, the findings highlight the mechanism underlying how EV-packaged circRNAs mediate the PNI of KRAS-mutant PDAC cells through the Rab5B endosomal bypass, identifying circPNIT as an effective target for the treatment of neuro-metastatic PDAC.

Molecular Profiling of Low-Grade Appendiceal Mucinous Neoplasms (LAMN).

Low-grade appendiceal mucinous neoplasia (LAMN) represents a relatively rare tumor of the appendix typically diagnosed incidentally through appendectomy for acute appendicitis. In cases where perforation occurs, mucinous content may disseminate into the abdominal cavity, leading to the development of pseudomyxoma peritonei (PMP). The primary objective of this study was to elucidate the molecular characteristics associated with various stages of LAMN and PMP. DNA was extracted from LAMN, primary PMPs, recurrent PMPs, and adenocarcinomas originating from LAMN. The subsequent analysis involved the examination of mutational hotspot regions within 50 cancer-related genes, covering over 2800 COSMIC mutations, utilizing amplicon-based next-generation sequencing (NGS). Our findings revealed activating somatic mutations within the MAPK-signaling pathway across all tumors examined. Specifically, 98.1% of cases showed mutations in KRAS, while one tumor harbored a BRAF mutation. Additionally, GNAS mutations were identified in 55.8% of tumors, with no significant difference observed between LAMN and PMP. While LAMN rarely displayed additional mutations, 42% of primary PMPs and 60% of recurrent PMPs showed additional mutations. Notably, both adenocarcinomas originating from LAMN showed mutations within TP53. Furthermore, 7.7% (4/52) of cases exhibited a potentially targetable KRAS G12C mutation. In four patients, NGS analysis was performed on both primary PMP and recurrent PMP/adenocarcinoma samples. While mutations in KRAS and GNAS were detected in almost all samples, 50% of recurrent cases displayed an additional SMAD4 mutation, suggesting a notable alteration during disease progression. Our findings indicate two key points: First, mutations within the MAPK pathway, particularly in KRAS, are evident across all tumors, along with a high frequency of GNAS mutations. Second, progression toward PMP or adenocarcinoma is associated with an accumulation of additional mutations within common oncogenic pathways.

Prediction of metachronous advanced colorectal neoplasia by KRAS mutation in polyps.

BACKGROUND: The potential of molecular markers in the removed polys as reliable predictors of metachronous lesions is still uncertain. AIM: Our aim was to evaluate the role of somatic mutations in KRAS in polyps of patients with high-risk adenomas to predict the risk of advanced polyps or colorectal cancer (CRC) within 3 years. METHODS: A total of 518 patients were prospectively enrolled. The included patients had adenomas ≥10 mm, high-grade dysplasia, villous component or ≥3 more adenomas at baseline and were scheduled to undergo surveillance colonoscopy at 3 years ± 6 months. Somatic KRAS mutation was performed on 1189 polyps collected from these patients. At surveillance, advanced lesions were defined as adenomas with a size of ≥10 mm. High-grade dysplasia or villous component, serrated polyps ≥10 mm or with dysplasia or CRC. RESULTS: At baseline, 81 patients (15.6%) had KRAS mutations in at least one polyp. Patients with KRAS mutated polyps had more frequent villous histological lesions and size ≥20 mm. In the multivariate analysis, adjusted for age and sex, only age (odds ratios [OR], 1.06; 95% confidence interval [CI], 1.02-1.09; p < 0.001), ≥5 adenomas (OR, 3.92; 95% CI, 1.96-7.82), and KRAS mutation (OR, 2.54; 95% CI, 1.48-4.34; p < 0.01) were independently associated with the development of advanced lesions at surveillance. CONCLUSIONS: Our results show that, in patients with high-risk adenomas, the presence of somatic mutations in KRAS is an independent risk factor for the development of advanced metachronous polyps.

Oral sialadenoma papilliferum with kras mutation in a patient with linear nevus sebaceous syndrome.

Linear nevus sebaceous syndrome (LNSS) is a rare neurocutaneous syndrome part of the epidermal nevus syndromes group, characterized by the presence of sebaceous nevi and other extracutaneous lesions genetically related to RAS family gene mutations. Sialadenoma papilliferum (SP) is a rare benign intraoral neoplasm which is usually BRAF or HRAS mutated. We report a case of a young female girl diagnosed with a LNSS who developed a SP which had a KRAS mutation. This is the first case of SP with a KRAS mutation in the context of a LNSS.

Dissecting the Clinical Characteristics and Treatment Outcomes Correlates of KRAS G12C-Mutated Non-Small Cell Lung Cancer.

Background: KRAS mutation is one of the most common driver oncogenes in non-small cell lung cancer (NSCLC), and the most common mutation subtype is G12C. However, there is still a lack of efficacy and prognosis data related to immunotherapy, which hinders the promotion of new strategies. Methods: Clinical characteristics and treatment outcomes were collected and analyzed for patients with NSCLC harboring KRAS mutations at West China Hospital of Sichuan University from June 2013 to March 2023. Results: Among the 231 patients with KRAS-mutated NSCLC, 29.4% had KRAS G12C mutations. Compared to the KRAS non-G12C NSCLC group, the KRAS G12C NSCLC group had a greater number of pack-years. The programmed death ligand 1 expression and the proportion of patients with a high tumor mutational burden were not significantly different between the two groups. Similar patterns of TP53, STK11, and CDKN2A mutations were observed between KRAS G12C and KRAS non-G12C NSCLC groups. The median progression-free survival (PFS) (8.4 vs 7.0 months, p=0.100) and overall survival (OS) (12.1 vs 18.1 months, p=0.590) were not statistically different between KRAS G12C and KRAS non-G12C. Compared to patients with KRAS G12C NSCLC who did not receive immunotherapy, patients who received immunotherapy had a better objective response rate (46.2% vs 0%, p=0.002), PFS (12.2 vs 7.5 months, p=0.087) and OS (49.9 vs 11.1 months, p=0.12). Conclusion: Patients with KRAS G12C were more likely to be smokers. Advanced KRAS G12C NSCLC patients who received immunotherapy had a better ORR than those who did not, suggesting that patients with G12C mutations are more likely to benefit from immunotherapy.

Treatment Strategies' Impact on Progression-Free Survival According to RMST Function in Metastatic Colorectal Cancer Patients: A Retrospective Study from Romania.

Background: This retrospective study investigates the impact of various treatment strategies on progression-free survival (PFS) in patients with metastatic colorectal cancer (mCRC), a significant global health issue. Methods: We employed the restricted mean survival time (RMST) to evaluate how different treatments affect PFS over a defined period. The study included 225 patients with mCRC who were treated between 2015 and 2023 at the Oncology Department of Colțea Clinical Hospital in Bucharest. To assign KRAS status, mutation data from exons 2, 3, and 4 of the KRAS gene were required. Eligibility criteria included a confirmed histopathological diagnosis of colorectal adenocarcinoma, a valid RAS mutation test from a solid biopsy, radiological confirmation of stage IV disease by computed tomography, and at least one line of systemic treatment in the metastatic setting. Results: Our analysis revealed a small difference in PFS based on KRAS status, but this difference was not statistically significant. Neither sex nor the urban versus rural environment impacted PFS; however, the data indicated that educational level affected survival outcomes. Conclusions: Consistent with existing literature, our findings showed no survival benefit from locoregional treatments such as surgery of the primary tumor or curative radiotherapy at diagnosis. In contrast, resection of hepatic metastases was associated with improved survival outcomes.

Sustained Response to Anti-PD-1 Therapy in Combination with Nab-Paclitaxel in Metastatic Testicular Germ Cell Tumor Harboring the KRAS-G12V Mutation: A Case Report.

INTRODUCTION: Cisplatin-based standardized therapy has been established for metastatic testicular germ cell tumors (TGCTs). However, the patient prognosis is considerably less favorable if the disease recurs following failure of first-line therapies. There is a need for novel treatment options for patients with recurrent or metastatic TGCTs, notably for those that are not sensitive to first-line chemotherapy. With the development of next-generation sequencing technologies, an increasing number of gene mutations has been identified in TGCTs. Previously published research studies have established a link between KRAS mutations and chemotherapy resistance, and have demonstrated that KRAS mutations are associated with inflammatory tumor microenvironment and tumor immunogenicity, leading to an improved response to inhibition of programmed death (PD-1) protein expression. Previous studies have reported that the tumor immune microenvironment of TGCT influences therapeutic efficacy. CASE PRESENTATION: A 65-year-old metastatic patient with TGCT and a KRAS-12 valine-for-glycine gene mutation was described. This patient initially underwent inguinal orchiectomy and received two prior chemotherapeutic regimens. Following the rapid progression of the disease, the patient was treated with anti-PD-1 therapy and nab-paclitaxel chemotherapy, and his condition was successfully controlled by this combination treatment. CONCLUSION: To the best of our knowledge, this is the first successful case of KRAS-mutation patient with TGCT who achieved partially and sustained disease remission by combining immune checkpoint inhibitors with chemotherapy. This case provides an excellent example for personalized treatment of metastatic TGCTs.

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.

Cell-specific models reveal conformation-specific RAF inhibitor combinations that synergistically inhibit ERK signaling in pancreatic cancer cells.

Pancreatic ductal adenocarcinoma (PDAC) presents significant challenges for targeted clinical interventions due to prevalent KRAS mutations, rendering PDAC resistant to RAF and MEK inhibitors (RAFi and MEKi). In addition, responses to targeted therapies vary between patients. Here, we explored the differential sensitivities of PDAC cell lines to RAFi and MEKi and developed an isogenic pair comprising the most sensitive and resistant PDAC cells. To simulate patient- or tumor-specific variations, we constructed cell-line-specific mechanistic models based on protein expression profiling and differential properties of KRAS mutants. These models predicted synergy between two RAFi with different conformation specificity (type I½ and type II RAFi) in inhibiting phospho-ERK (ppERK) and reducing PDAC cell viability. This synergy was experimentally validated across all four studied PDAC cell lines. Our findings underscore the need for combination approaches to inhibit the ERK pathway in PDAC.

Macroautophagy/autophagy promotes resistance to KRASG12D-targeted therapy through glutathione synthesis.

KRASG12D mutation-driven pancreatic ductal adenocarcinoma (PDAC) represents a major challenge in medicine due to late diagnosis and treatment resistance. Here, we report that macroautophagy (hereafter autophagy), a cellular degradation and recycling process, contributes to acquired resistance against novel KRASG12D-targeted therapy. The KRASG12D protein inhibitor MRTX1133 induces autophagy in KRASG12D-mutated PDAC cells by blocking MTOR activity, and increased autophagic flux prevents apoptosis. Mechanistically, autophagy facilitates the generation of glutamic acid, cysteine, and glycine for glutathione synthesis. Increased glutathione levels reduce reactive oxygen species production, which impedes CYCS translocation from mitochondria to the cytosol, ultimately preventing the formation of the APAF1 apoptosome. Consequently, genetic interventions (utilizing ATG5 or BECN1 knockout) or pharmacological inhibition of autophagy (with chloroquine, bafilomycin A1, or spautin-1) enhance the anticancer activity of MRTX1133 in vitro and in various animal models (subcutaneous, patient-derived xenograft, and orthotopic). Moreover, the release of histones by apoptotic cells triggers an adaptive immune response when combining an autophagy inhibitor with MRTX1133 in immunocompetent mice. These findings establish a new strategy to overcome KRASG12D-targeted therapy resistance by inhibiting autophagy-dependent glutathione synthesis.

Pseudomyxoma Peritonei Arising From a Mucinous Ovarian Borderline Tumor Treated With Paclitaxel, Cisplatin, and Bevacizumab: A Case Report.

Pseudomyxoma peritonei (PMP) is a rare disease caused by primary mucinous neoplasms. Here, we describe a case where a large ovarian tumor was initially removed laparoscopically, followed by an appendectomy. The patient was diagnosed with PMP arising from an ovarian mucinous borderline tumor with a KRAS mutation. Treatment included bevacizumab-containing chemotherapy, resulting in complete remission.

Immune status and combined immunotherapy progression in Kirsten rat sarcoma viral oncogene homolog (KRAS)-mutant tumors.

Kirsten rat sarcoma viral oncogene homolog (KRAS) is the most frequently mutated oncogene, occurring in various tumor types. Despite extensive efforts over the past 40 years to develop inhibitors targeting KRAS mutations, resistance to these inhibitors has eventually emerged. A more precise understanding of KRAS mutations and the mechanism of resistance development is essential for creating novel inhibitors that target specifically KRAS mutations and can delay or overcome resistance. Immunotherapy has developed rapidly in recent years, and in-depth dissection of the tumor immune microenvironment has led researchers to shift their focus to patients with KRAS mutations, finding that immune factors play an essential role in KRAS-mutant (KRAS-Mut) tumor therapy and targeted drug resistance. Breakthroughs and transitions from targeted therapy to immunotherapy have provided new hope for treating refractory patients. Here, we reviewed KRAS mutation-targeted treatment strategies and resistance issues, focusing on our in-depth exploration of the specific immune status of patients with KRAS mutations and the impact of body immunity following KRAS inhibition. We aimed to guide innovative approaches combining RAS inhibition with immunotherapy, review advances in preclinical and clinical stages, and discuss challenges and future directions.

Diagnostic and therapeutic strategies in pancreatic adenosquamous carcinoma: Molecular and clinical insights in managing metastatic disease.

Adenosquamous carcinoma of the pancreas (ASCP) is a rare and aggressive variant of pancreatic cancer, characterized by both adenocarcinoma and squamous cell carcinoma components. It presents significant diagnostic and therapeutic challenges due to its atypical histology and poor prognosis. A 72-year-old male presented with abdominal pain, lighter-colored stools, and intermittent nausea. Initial imaging revealed a complex mass in the distal pancreatic body and tail. Elevated lipase levels and subsequent endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) suggested an atypical pancreatic lesion with keratinizing squamous cells. Further investigation through fiberoptic bronchoscopy and EBUS-guided transbronchial needle aspiration (TBNA) confirmed carcinoma with squamous differentiation. Genetic testing identified KRAS G12D and PIK3CA mutations. The multidisciplinary tumor board recommended systemic chemotherapy with mFOLFIRINOX and G-CSF support. The patient underwent twelve cycles of mFOLFIRINOX with dose adjustments for thrombocytopenia and effective management of chemotherapy-related side effects. Restaging CT scans showed a decrease in tumor size and stable metastatic nodes. The patient showed a partial biochemical response with decreasing CA 19-9 levels and disease stabilization on imaging. This case demonstrates the critical role of a multidisciplinary approach in managing rare pancreatic malignancies. ASCP requires a comprehensive diagnostic and therapeutic strategy involving advanced imaging, histopathological confirmation, and personalized chemotherapy. Integrating advanced diagnostic techniques, molecular profiling, and a multidisciplinary approach is essential for improving patient outcomes and providing comprehensive care for this challenging malignancy. Addressing the psychological aspects and offering compassionate care are vital for supporting patients through their treatment journey.

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.

Association of KRAS Mutation and Gene Pathways in Colorectal Carcinoma: A Transcriptome- and Methylome-Wide Study and Potential Implications for Therapy.

Kirsten Rat Sarcoma (KRAS) is the most commonly mutated oncogene in colorectal carcinoma (CRC). We have previously reported the interactions between microsatellite instability (MSI), DNA promoter methylation, and gene expression. In this study, we looked for associations between KRAS mutation, gene expression, and methylation that may help with precision medicine. Genome-wide gene expression and DNA methylation were done in paired CRC tumor and surrounding healthy tissues. The results suggested that (a) the magnitude of dysregulation of many major gene pathways in CRC was significantly greater in patients with the KRAS mutation, (b) the up- and down-regulation of these dysregulated gene pathways could be correlated with the corresponding hypo- and hyper-methylation, and (c) the up-regulation of CDKN2A was more pronounced in tumors with the KRAS mutation. A recent cell line study showed that there were higher CDKN2A levels in 5-FU-resistant CRC cells and that these could be down-regulated by Villosol. Our findings suggest the possibility of a better response to anti-CDKN2A therapy with Villosol in KRAS-mutant CRC. Also, the more marked up-regulation of genes in the proteasome pathway in CRC tissue, especially with the KRAS mutation and MSI, may suggest a potential role of a proteasome inhibitor (bortezomib, carfilzomib, or ixazomib) in selected CRC patients if necessary.

CHNet: A multi-task global-local Collaborative Hybrid Network for KRAS mutation status prediction in colorectal cancer.

Accurate prediction of Kirsten rat sarcoma (KRAS) mutation status is crucial for personalized treatment of advanced colorectal cancer patients. However, despite the excellent performance of deep learning models in certain aspects, they often overlook the synergistic promotion among multiple tasks and the consideration of both global and local information, which can significantly reduce prediction accuracy. To address these issues, this paper proposes an innovative method called the Multi-task Global-Local Collaborative Hybrid Network (CHNet) aimed at more accurately predicting patients' KRAS mutation status. CHNet consists of two branches that can extract global and local features from segmentation and classification tasks, respectively, and exchange complementary information to collaborate in executing these tasks. Within the two branches, we have designed a Channel-wise Hybrid Transformer (CHT) and a Spatial-wise Hybrid Transformer (SHT). These transformers integrate the advantages of both Transformer and CNN, employing cascaded hybrid attention and convolution to capture global and local information from the two tasks. Additionally, we have created an Adaptive Collaborative Attention (ACA) module to facilitate the collaborative fusion of segmentation and classification features through guidance. Furthermore, we introduce a novel Class Activation Map (CAM) loss to encourage CHNet to learn complementary information between the two tasks. We evaluate CHNet on the T2-weighted MRI dataset, and achieve an accuracy of 88.93% in KRAS mutation status prediction, which outperforms the performance of representative KRAS mutation status prediction methods. The results suggest that our CHNet can more accurately predict KRAS mutation status in patients via a multi-task collaborative facilitation and considering global-local information way, which can assist doctors in formulating more personalized treatment strategies for patients.

The effects of KRAS Mutations on the Prognosis of Rectal Cancer Following Neoadjuvant Chemoradiotherapy and Surgery.

BACKGROUND: Rectal cancers with mutations in the KRAS gene have worse prognoses than wild-type malignancies. Variants at codon 12 of KRAS have particularly detrimental effects on prognosis. We aimed to analyze whether KRAS mutations act as adverse prognostic factors following neoadjuvant concurrent chemoradiotherapy (CRT) and surgery for rectal cancer treatment. METHODS: We analyzed the effects of KRAS mutations on disease-free survival (DFS) and locoregional recurrence-free survival (LRFS) in 125 patients with cT2-4N0-2M0 rectal cancer who underwent surgery following CRT between June 2014 and March 2023 Inje University Busan Paik Hospital. RESULTS: The median follow-up period was 39.7 (range, 7.5-98.2) months. There were 25 patients (20.0%) who harbored KRAS mutations. Among them, 22 patients (17.6%) had codon 12 variants. Overall, 43 patients (34.4%) showed recurrence, of which 10 (8.0%) had locoregional recurrence and 35 (28.0%) had distant metastases (two occurred simultaneously). DFS was significantly reduced in the patients with KRAS mutations (p = 0.005). LRFS was also reduced in patients with KRAS mutations (p = 0.039). DFS and LRFS were also relatively low in the subgroup with KRAS mutations at codon 12 (n = 22) (p = 0.003 and p = 0.017, respectively). However, pathologic complete response rate following CRT was not affected by KRAS mutations (p = 0.197). Overall survival was also not associated with KRAS mutations (p = 0.486). CONCLUSION: KRAS mutation is related to decreased DFS and LRFS, when surgery is performed following neoadjuvant CRT to treat rectal cancer. These effects are particularly pronounced for KRAS mutations at codon 12.

Assessment of KRASG12C inhibitors for colorectal cancer.

Colorectal cancer (CRC) is a highly prevalent and lethal cancer worldwide. Approximately 45% of CRC patients harbor a gain-in-function mutation in KRAS. KRAS is the most frequently mutated oncogene accounting for approximately 25% of all human cancers. Gene mutations in KRAS cause constitutive activation of the KRAS protein and MAPK/AKT signaling, resulting in unregulated proliferation and survival of cancer cells and other aspects of malignant transformation, progression, and metastasis. While KRAS has long been considered undruggable, the FDA recently approved two direct acting KRAS inhibitors, Sotorasib and Adagrasib, that covalently bind and inactivate KRASG12C. Both drugs showed efficacy for patients with non-small cell lung cancer (NSCLC) diagnosed with a KRASG12C mutation, but for reasons not well understood, were considerably less efficacious for CRC patients diagnosed with the same mutation. Thus, it is imperative to understand the basis for resistance to KRASG12C inhibitors, which will likely be the same limitations for other mutant specific KRAS inhibitors in development. This review provides an update on clinical trials involving CRC patients treated with KRASG12C inhibitors as a monotherapy or combined with other drugs. Mechanisms that contribute to resistance to KRASG12C inhibitors and the development of novel RAS inhibitors with potential to escape such mechanisms of resistance are also discussed.