Treatment Of Advanced Colorectal Cancer Research Articles

Fisetin and/or capecitabine causes changes in apoptosis pathways in capecitabine-resistant colorectal cancer cell lines.

Capecitabine is recommended as one of the first-line chemotherapy treatments for advanced or metastatic colorectal cancer. Researches have been conducted on capecitabine's impact on the viability of human colon cancer cells and its potential to induce apoptosis. However, even in cases initially responsive to treatment, the development of acquired resistance significantly limits its efficacy. Challenges still exist in effectively treating patients with chemotherapy, and developing new cytotoxic drugs is hindered by drug resistance. Fisetin alters the cell cycle, inducing apoptosis, inhibiting cancer cell proliferation, and enhancing the therapeutic effectiveness of chemotherapy drugs. This work aims to create a plan for reversing capecitabine resistance. For this purpose, the role of capecitabine and/or fisetin combinations in cell proliferation and apoptosis has been determined in both wild-type and capecitabine-resistant HT29 cells (CR/HT29). We developed capecitabine-resistant cell line from wild-type HT29 cells. This study demonstrated the effects of capecitabine, fisetin, and their combinations on both resistant and wild-type cells through experiments including cell survival skills, cell proliferation, wound healing, colony formation, hoechst staining, and western blot analysis.We established capecitabine-resistant cell lines. P-gp expression increased in CR/HT29 cells. Capecitabine effects on a CR/HT29 cells less than wild-type HT29 cells. The combination of fisetin and capecitabine in cell proliferation caused greater reductions in wild-type HT29 cells than in capecitabine-resistant cells. Fisetin has also additive effects on the apoptotic pathway in CR/HT29 cells.This study provides new perspectives on the combination of capecitabine and/or flavonoid treatment in resistant cells.

LncRNA GAS6-AS1 contributes to 5-fluorouracil resistance in colorectal cancer by facilitating the binding of PCBP1 with MCM3

5-Fluorouracil (5-FU) resistance has always been a formidable obstacle in the adjuvant treatment of advanced colorectal cancer (CRC). In recent years, long non-coding RNAs have emerged as key regulators in various pathophysiological processes including 5-FU resistance. TRG is a postoperative pathological score of the chemotherapy effectiveness for CRC, of which TRG 0–1 is classified as chemotherapy sensitivity and TRG 3 as chemotherapy resistance. Here, RNA-seq combined with weighted gene correlation network analysis confirmed the close association of GAS6-AS1 with TRG. GAS6-AS1 expression was positively correlated with advanced clinicopathological features and poor prognosis in CRC. GAS6-AS1 increased the 50% inhibiting concentration of 5-FU, enhanced cell proliferation and accelerated G1/S transition, both with and without 5-FU, both in vitro and in vivo. Mechanistically, GAS6-AS1 enhanced the stability of MCM3 mRNA by recruiting PCBP1, consequently increasing MCM3 expression. Furthermore, PCBP1 and MCM3 counteracted the effects of GAS6-AS1 on 5-FU resistance. Notably, the PDX model indicated that combining chemotherapeutic drugs with GAS6-AS1 knockdown yielded superior outcomes in vivo. Together, our findings elucidate that GAS6-AS1 directly binds to PCBP1, enhancing MCM3 expression and thereby promoting 5-FU resistance. GAS6-AS1 may serve as a robust biomarker and potential therapeutic target for combination therapy in CRC.

Abstract 1728: Senescent cancer-associated fibroblast drives colorectal cancer progression in a METTL1-dependent manner

Abstract Background: Colorectal cancer (CRC) is a leading cause of cancer-related mortality worldwide. More comprehensive studies of key molecular alterations were urgent. Cancer-associated fibroblasts (CAFs) exhibit the senescence-associated secretory phenotype (SASP) which contributes to the progression of cancer through the transcriptomic reprogramming at their senescent states. N7-methylguanosine (m7G), one of the most common RNA modifications, is catalyzed by Methyltransferase-like 1 (METTL1) in human RNA. We therefore investigated the role of METTL1-mediated transcriptomic reprogramming in the crosstalk between senescent CAFs (s-CAFs) and cancer cells. Methods: The SA-β-gal staining and immunofluorescence assays were conducted to characterize the senescent cells. The transwell, wound scratch and organoids assays were preformed to test the abilities of viability, migration and invasion. The concentrations of cytokines and chemokines were determined by Luminex liquid suspension chip. The methylated RNA immunoprecipitation and dot blot assays were performed to characterize the RNA m7G levels in the transcriptome. Results: Through the activation of mTOR signaling, the expression of P16 gene was significantly up-regulated in s-CAFs which was treated by H2O2, accompanied by an increased proportion of SA-β-gal+ cells and altered expression level of METTL1 protein. Luminex liquid suspension chip analysis revealed a significant increase in SASP cytokines such as TNF-α and PDGF-BB in the conditioned media of s-CAFs. Co-culturing CRC cell and organoids with s-CAFs resulted in down-regulation of METTL1 expression and significantly enhanced its invasion and migration abilities, while organoids exhibited increased activity and proliferated more rapidly. TNF-α and PDGF-BB down-regulated the METTL1 expression in CRC cell, while inhibitors targeting TNF-α and PDGF-BB rescued this trend. Interestingly, the regulatory effect on METTL1 of CRC cell by s-CAFs which treated by rapamycin was disappeared. These results indicated that METTL1 modulates RNA m7G modifications influenced by SASP cytokines for promoting CRC metastasis flow. Conclusions: In summary, our findings illustrated that METTL1 plays a role in relaying tumor-promoting signals from s-CAFs in response to SASP cytokines. This ultimately contributes to the tumor-promoting signal flow from s-CAFs. This highlights the importance of understanding the molecular mechanisms underlying the communication between different cell types in the tumor microenvironment. In addition, it also provides a novel strategy for clinical treatment in advanced CRC. Keywords: METTL1, Epigenetic regulation, Senescent CAFs, Tumor microenvironment Citation Format: Jingrong Weng, Xiaolin Wang, Xiaoxia Liu, Yanxin Luo, Huichuan Yu. Senescent cancer-associated fibroblast drives colorectal cancer progression in a METTL1-dependent manner [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1728.

CircHAS2 activates CCNE2 to promote cell proliferation and sensitizes the response of colorectal cancer to anlotinib

BackgroundTyrosine kinase inhibitors (TKIs) are crucial in the targeted treatment of advanced colorectal cancer (CRC). Anlotinib, a multi-target TKI, has previously been demonstrated to offer therapeutic benefits in previous studies. Circular RNAs (circRNAs) have been implicated in CRC progression and their unique structural stability serves as promising biomarkers. The detailed molecular mechanisms and specific biomarkers related to circRNAs in the era of targeted therapies, however, remain obscure.MethodsThe whole transcriptome RNA sequencing and function experiments were conducted to identify candidate anlotinib-regulated circRNAs, whose mechanism was confirmed by molecular biology experiments. CircHAS2 was profiled in a library of patient-derived CRC organoids (n = 22) and patient-derived CRC tumors in mice. Furthermore, a prospective phase II clinical study of 14 advanced CRC patients with anlotinib-based therapy was commenced to verify drug sensitivity (ClinicalTrials.gov identifier: NCT05262335).ResultsAnlotinib inhibits tumor growth in vitro and in vivo by downregulating circHAS2. CircHAS2 modulates CCNE2 activation by acting as a sponge for miR-1244, and binding to USP10 to facilitate p53 nuclear export as well as degradation. In parallel, circHAS2 serves as a potent biomarker predictive of anlotinib sensitivity, both in patient-derived organoids and xenograft models. Moreover, the efficacy of anlotinib inclusion into the treatment regimen yields meaningful clinical responses in patients with high levels of circHAS2. Our findings offer a promising targeted strategy for approximately 52.9% of advanced CRC patients who have high circHAS2 levels.ConclusionsCircHAS2 promotes cell proliferation via the miR-1244/CCNE2 and USP10/p53/CCNE2 bidirectional axes. Patient-derived organoids and xenograft models are employed to validate the sensitivity to anlotinib. Furthermore, our preliminary Phase II clinical study, involving advanced CRC patients treated with anlotinib, confirmed circHAS2 as a potential sensitivity marker.

Is Older Age an Independent Prognostic Factor of Survival in Metastatic Colorectal Cancer?

Plain Language SummaryOlder patients with advanced CRC constitute a heterogeneous population, including patients with excellent health status and others with multiple comorbidities, functional dependence, or limited life expectancy. Furthermore, the definition of an “elderly” or “older” patient is not widely accepted and may vary between studies, although 75 years may be an appropriate cut-off point, as confirmed in our study. At present, there are few prospective and randomized studies focused on the progression and treatment of advanced colorectal cancer in elderly patients, so understanding the factors that influence its clinical course is a difficult challenge. In this retrospective real-world study, we analyze the influence of advanced age on the survival of patients with advanced colorectal cancer. The analysis of eighteen characteristics that were grouped in three subcategories: characteristic related to the patient (age, sex, comorbidities, polypharmacy, ECOG, and nutritional status [albumin levels at diagnosis]), to the tumor (stage at diagnosis, tumor side, molecular profile, tumor burden [CEA levels at diagnosis], location and number of metastasis), and to the treatment administrated (systemic treatment for advanced disease, chemotherapy schedule and number of lines, severe adverse events and dose reductions, and surgery of liver metastasis) showed that older age at diagnosis is not an independent prognostic factor of overall survival in patients with metastatic colorectal cancer. However, tumor burden, nutritional status, systemic treatment of advanced disease, or surgery of liver metastases are independent predictors of survival.

Controversial role of γδ T cells in colorectal cancer.

Colorectal cancer (CRC) is the third most frequent type of cancer, and the second leading cause of cancer-related deaths worldwide. Current treatments for patients with CRC do not substantially improve the survival and quality of life of patients with advanced CRC, thus necessitating the development of new treatment strategies. The emergence of immunotherapy has revitalized the field, showing great potential in advanced CRC treatment. Owing to the ability of tumor cells to evade the immune system through major histocompatibility complex shedding and heterogeneous and low antigen spreading, only a few patients respond to immunotherapy. γδ T cells have heterogeneous structures and functions, and their key roles in immune regulation, tumor immunosurveillance, and specific primary immune responses have increasingly been recognized. γδ T cells recognize and kill CRC cells efficiently, thus inhibiting tumor progress through various mechanisms. However, γδ T cells can potentially promote tumor development and metastasis. Thus, given this dual role in prognosis, these cells can act as either a "friend" or "foe" of CRC. In this review, we explore the characteristics of γδ T cells and their functions in CRC, highlighting their application in immunotherapy.

Study on prediction of early adverse events by CapeOX therapy in patients with colorectal cancer.

CapeOX is a regimen used as postoperative adjuvant chemotherapy for the treatment of advanced recurrent colorectal cancer. If early adverse events occur, treatment may not progress as planned and further dose reduction may be necessary. In this study, we investigated whether pre-treatment medical records could be used to predict adverse events in order to prevent adverse events caused by CapeOX treatment. The 178 patients were classified into two groups (97 in the adverse event positive group and 81 in the adverse event-negative group) based on withdrawal or postponement of four or fewer courses. In univariate analysis, age, height, weight, body surface area (BSA), creatinine clearance, muscle mass, and lean body mass were associated with early adverse events (P<0.05). The area under the receiver operating characteristic curve obtained by Stepwise logistic regression analysis using the Akaike information criterion method was 0.832. For nested k-fold cross validation, the accuracy rates of the support vector machine, random forest, and logistic regression algorithms were 0.71, 0.70, and 0.75, respectively. The results of the present study suggest that a logistic regression prediction model may be useful in predicting early adverse events caused by CapeOX therapy in patients with colorectal cancer. J. Med. Invest. 71 : 141-147, February, 2024.

Liver Metastases and Immune Checkpoint Inhibitor Efficacy in Patients With Refractory Metastatic Colorectal Cancer

Immune checkpoint inhibitors (ICIs) have limited activity in microsatellite-stable (MSS) or mismatch repair-proficient (pMMR) colorectal cancer. Recent findings suggest the efficacy of ICIs may be modulated by the presence of liver metastases (LM). To investigate the association between the presence of LM and ICI activity in advanced MSS colorectal cancer. In this secondary analysis of the Canadian Cancer Trials Group CO26 (CCTG CO.26) randomized clinical trial, patients with treatment-refractory colorectal cancer were randomized in a 2:1 fashion to durvalumab plus tremelimumab or best supportive care alone between August 10, 2016, and June 15, 2017. The primary end point was overall survival (OS) with 80% power and 2-sided α = .10. The median follow-up was 15.2 (0.2-22.0) months. In this post hoc analysis performed from February 11 to 14, 2022, subgroups were defined based on the presence or absence of LM and study treatments. Durvalumab plus tremelimumab or best supportive care. Hazard ratios (HRs) and 90% CIs were calculated based on a stratified Cox proportional hazards regression model. Plasma tumor mutation burden at study entry was determined using a circulating tumor DNA assay. The primary end point of the study was OS, defined as the time from randomization to death due to any cause; secondary end points included progression-free survival (PFS) and disease control rate (DCR). Of 180 patients enrolled (median age, 65 [IQR, 36-87] years; 121 [67.2%] men; 19 [10.6%] Asian, 151 [83.9%] White, and 10 [5.6%] other race or ethnicity), LM were present in 127 (70.6%). For patients with LM, there was a higher proportion of male patients (94 of 127 [74.0%] vs 27 of 53 [50.9%]; P = .005), and the time from initial cancer diagnosis to study entry was shorter (median, 40 [range, 8-153] vs 56 [range, 14-181] months; P = .001). Plasma tumor mutation burden was significantly higher in patients with LM. Patients without LM had significantly improved PFS with durvalumab plus tremelimumab (HR, 0.54 [90% CI, 0.35-0.96]; P = .08; P = .02 for interaction). Disease control rate was 49% (90% CI, 36%-62%) in patients without LM treated with durvalumab plus tremelimumab, compared with 14% (90% CI, 6%-38%) in those with LM (odds ratio, 5.70 [90% CI, 1.46-22.25]; P = .03). On multivariable analysis, patients without LM had significantly improved OS and PFS compared with patients with LM. In this secondary analysis of the CCTG CO.26 study, the presence of LM was associated with worse outcomes for patients with advanced colorectal cancer. Patients without LM had improved PFS and higher DCR with durvalumab plus tremelimumab. Liver metastases may be associated with poor outcomes of ICI treatment in advanced colorectal cancer and should be considered in the design and interpretation of future clinical studies evaluating this therapy.

ZNF746 plays cardinal roles on colorectal cancer (CRC) cell invasion and migration and regulates mitochondrial dynamics and morphological changes of CRC cells-Role of combined melatonin and 5-FU regimen.

The underlying mechanism of colorectal cells developing into cancer cells has been extensively investigated, yet is still not fully delineated, resulting in the treatment of advanced colorectal cancer (CRC) remains regrettably an unmet need. Zinc Finger Protein 746/Parkin-interacting substrate (ZNF746/PARIS) has previously been identified to play a fundamental role on bladder cancer cell proliferation and metastasis that were effectively inhibited by melatonin (Mel). In this study, we utilized ex vivo/in vivo studies to verify whether the ZNF746 signaling was also crucial in CRC growth/invasion/migration. Tissue-bank specimens showed that the protein expression of ZNF746 was significantly increased in CRC than that of healthy colorectal tissues (p < 0.001). Additionally, in vitro study demonstrated that excessive expression of ZNF746 significantly inhibited mitochondrial activity via (1) interfering with the dynamic balance of mitochondrial fusion/fission and (2) inhibiting the protein expression of MFN1/MFN2/PGC1a (all p < 0.001). Furthermore, we identified that inhibition of ZNF746 protein expression significantly reduced the resistance of CRC cell lines to the anticancer drug of 5-FU (p < 0.001), whereas overexpression of ZNF746 significantly augmented resistance of CRC cells to 5-FU (all p < 0.001). Finally, using the cell culture method, we found that combined Mel and 5-FU was superior to merely one on promoting the CRC cell apoptosis (p < 0.001). Our results confirmed that ZNF746 signaling played a cardinal role of CRC cell proliferation/survival and combined Mel and 5-FU treatment attenuated the resistance of CRC cells to the drug mainly through suppressing this signaling.

Anti-PD-1/PD-L1 therapy for colorectal cancer: Clinical implications and future considerations

Colorectal cancer (CRC) is the third most prevalent cancer in the world. The PD-1/PD-L1 pathway plays a crucial role in modulating immune response to cancer, and PD-L1 expression has been observed in tumor and immune cells within the tumor microenvironment of CRC. Thus, immunotherapy drugs, specifically checkpoint inhibitors, have been developed to target the PD-1/PD-L1 signaling pathway, thereby inhibiting the interaction between PD-1 and PD-L1 and restoring T-cell function in cancer cells. However, the emergence of resistance mechanisms can reduce the efficacy of these treatments. To counter this, monoclonal antibodies (mAbs) have been used to improve the efficacy of CRC treatments. mAbs such as nivolumab and pembrolizumab are currently approved for CRC treatment. These antibodies impede immune checkpoint receptors, including PD-1/PD-L1, and their combination therapy shows promise in the treatment of advanced CRC. This review presents a concise overview of the use of the PD-1/PD-L1 blockade as a therapeutic strategy for CRC using monoclonal antibodies and combination therapies. Additionally, this article outlines the function of PD-1/PD-L1 as an immune response suppressor in the CRC microenvironment as well as the potential advantages of administering inflammatory agents for CRC treatment. Finally, this review analyzes the outcomes of clinical trials to examine the challenges of anti-PD-1/PD-L1 therapeutic resistance.

Leucovorin and Fluorouracil With or Without Oxaliplatin as First-Line Treatment in Advanced Colorectal Cancer.

In a previous study of treatment for advanced colorectal cancer, the LV5FU2 regimen, comprising leucovorin (LV) plus bolus and infusional fluorouracil (5FU) every 2 weeks, was superior to the standard North Central Cancer Treatment Group/Mayo Clinic 5-day bolus 5FU/LV regimen. This phase III study investigated the effect of combining oxaliplatin with LV5FU2, with progression-free survival as the primary end point. Four hundred twenty previously untreated patients with measurable disease were randomized to receive a 2-hour infusion of LV (200 mg/m2/d) followed by a 5FU bolus (400 mg/m2/d) and 22-hour infusion (600 mg/m2/d) for 2 consecutive days every 2 weeks, either alone or together with oxaliplatin 85 mg/m2 as a 2-hour infusion on day 1. Patients allocated to oxaliplatin plus LV5FU2 had significantly longer progression-free survival (median, 9.0 v 6.2 months; P = .0003) and better response rate (50.7% v 22.3%; P = .0001) when compared with the control arm. The improvement in overall survival did not reach significance (median, 16.2 v 14.7 months; P = .12). LV5FU2 plus oxaliplatin gave higher frequencies of National Cancer Institute common toxicity criteria grade 3/4 neutropenia (41.7% v 5.3% of patients), grade 3/4 diarrhea (11.9% v 5.3%), and grade 3 neurosensory toxicity (18.2% v 0%), but this did not result in impairment of quality of life (QoL). Survival without disease progression or deterioration in global health status was longer in patients allocated to oxaliplatin treatment (P = .004). The LV5FU2-oxaliplatin combination seems beneficial as first-line therapy in advanced colorectal cancer, demonstrating a prolonged progression-free survival with acceptable tolerability and maintenance of QoL.

Randomised, placebo-controlled, phase 3 trial of the effect of the omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA) on colorectal cancer recurrence and survival after surgery for resectable liver metastases: EPA for Metastasis Trial 2 (EMT2) study protocol

IntroductionThere remains an unmet need for safe and cost-effective adjunctive treatment of advanced colorectal cancer (CRC). The omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA) is safe, well-tolerated and has anti-inflammatory...

TGF-β in correlation with tumor progression, immunosuppression and targeted therapy in colorectal cancer.

Colorectal cancer (CRC) is a complex malignancy responsible for the second-highest cancer deaths worldwide. TGF-β maintains normal cellular homeostasis by inhibiting the cell cycle and inducing apoptosis, but its elevated level is correlated with colorectal cancer progression, as TGF-β is a master regulator of the epithelial-to-mesenchymal transition, a critical step of metastasis. Tumors, including CRC, use elevated TGF-β levels to avoid immune surveillance by modulating immune cell differentiation, proliferation, and effector function. Presently, the treatment of advanced CRC is mainly based on chemotherapy, with multiple adverse effects. Thus, there is a need to develop alternate tactics because CRC continue to be mostly resistant to the present therapeutic regimen. TGF-β blockade has emerged as a promising therapeutic target in cancer therapy. Blocking TGF-β with phytochemicals and other molecules, such as antisense oligonucleotides, monoclonal antibodies, and bifunctional traps, alone or in combination, may be a safer and more effective way to treat CRC. Furthermore, combination immunotherapy comprising TGF-β blockers and immune checkpoint inhibitors is gaining popularity because both molecules work synergistically to suppress the immune system. Here, we summarize the current understanding of TGF-β as a therapeutic target for managing CRC and its context-dependent tumor-promoting or tumor-suppressing nature.

623P VIC regimen (vemurafenib/irinotecan/cetuximab) versus bevacizumab plus chemotherapy as first-line treatment for BRAF V600E-mutated advanced colorectal cancer

623P VIC regimen (vemurafenib/irinotecan/cetuximab) versus bevacizumab plus chemotherapy as first-line treatment for BRAF V600E-mutated advanced colorectal cancer

Matrix stiffness triggers lipid metabolic crosstalk between tumor and stromal cells to mediate bevacizumab resistance in colorectal cancer liver metastases.

Bevacizumab is an anti-vascular endothelial growth factor (VEGF) monoclonal antibody that plays an important role in the combination treatment of advanced colorectal cancer (CRC). However, resistance remains a major hurdle limiting bevacizumab efficacy, highlighting the importance of identifying mechanism of anti-angiogenic therapy resistance. Here, we investigated biophysical properties of the extracellular matrix (ECM) related to metabolic processes and acquired resistance to bevacizumab. Evaluation of paired pre- and post-treatment samples of liver metastases from 20 CRC patients treated with combination bevacizumab therapy, including 10 responders and 10 non-responders, indicated that ECM deposition in liver metastases and a highly activated fatty acid oxidation (FAO) pathway were elevated in non-responders after anti-angiogenic therapy compared to responders. In mouse models of liver metastatic CRC, anti-VEGF increased ECM deposition and FAO in CRC cells, and treatment with the FAO inhibitor etomoxir enhanced the efficacy of antiangiogenic therapy. Hepatic stellate cells (HSCs) were essential for matrix stiffness-mediated FAO in colon cancer cells. Matrix stiffness activated lipolysis in HSCs via the focal adhesion kinase (FAK)/yes-associated protein (YAP) pathway, and free fatty acids secreted by HSCs were absorbed as metabolic substrates and activated FAO in colon cancer cells. Suppressing HSC lipolysis using FAK and YAP inhibition enhanced the efficacy of anti-VEGF therapy. Together, these results indicate that bevacizumab-induced ECM remodeling triggers lipid metabolic crosstalk between colon cancer cells and HSCs. This metabolic mechanism of bevacizumab resistance mediated by the physical tumor microenvironment represents a potential therapeutic target for reversing drug resistance.

Carrilizumab for treatment of advanced colorectal cancer: Short-term efficacy and impact on immune function and PD-1/PD-L1 signaling pathway

Carrilizumab for treatment of advanced colorectal cancer: Short-term efficacy and impact on immune function and PD-1/PD-L1 signaling pathway

Single-cell analysis reveals cellular reprogramming in advanced colon cancer following FOLFOX-bevacizumab treatment.

The combination of FOLFOX and bevacizumab (FOLFOX-Bev) is a promising treatment for advanced colorectal cancer (CRC). However, the response of the tumor microenvironment to FOLFOX-Bev is still largely unexplored. We conducted single-cell transcriptomic analysis of CRC samples derived from a patient before and after treatment to gain insights into the cellular changes associated with FOLFOX-Bev treatment. We found that cancer cells with high proliferative, metastatic, and pro-angiogenic properties respond better to FOLFOX-Bev treatment. Moreover, FOLFOX-Bev enhances CD8+ T cell cytotoxicity, thereby boosting the anti-tumor immune response. Conversely, FOLFOX-Bev impairs the functionality of tumor-associated macrophages, plasma cells, and cancer-associated fibroblasts, leading to a decrease in VEGFB-mediated angiogenesis. Furthermore, FOLFOX-Bev treatment reset intercellular communication, which could potentially affect the function of non-cancer cells. Our findings provide valuable insights into the molecular mechanisms underlying the response of advanced CRC to FOLFOX-Bev treatment and highlight potential targets for improving the efficacy of this treatment strategy.

A validated LC-MS/MS method for the quantification of bevacizumab in rat, cynomolgus monkey, and human serum

Bevacizumab is a humanized monoclonal antibody used in the treatment of advanced colorectal and non-small cell lung cancer. Our main aim was to establish a simple, economical, and high efficiency liquid chromatography tandem mass spectrometry (LC-MS/MS) method for quantifying the content of bevacizumab in various biological fluids (rat, cynomolgus monkey, and human serum). A surrogate peptide of bevacizumab, specifically FTFSLDTSK, was generated through trypsin hydrolysis, and quantified using an isotopically labeled peptide containing two amino acids, FTFSLDTSK[13C6, 15N2]ST, as an internal standard to correct for variations introduced during the enzymatic hydrolysis process and any mass spectrometry variabilities. The pre-treatment process included denaturation, disulfide bond reduction and alkylation, trypsin hydrolysis, and termination of the reaction, with a total duration of approximately 2.5–3 h. The results of the methodological validation showed that the linear range in three different biological matrices was 0.2 µg/mL to300 µg/mL, with an LLOQ of 0.2 µg/mL. The precision and accuracy of the measurements met the required standards. The validated LC-MS/MS method was used to conduct pharmacokinetic analysis in rats administered bevacizumab at a dose of 10 mg/kg intravenously.

A Randomized Controlled Trial of Fluorouracil Plus Leucovorin, Irinotecan, and Oxaliplatin Combinations in Patients With Previously Untreated Metastatic Colorectal Cancer.

Three agents with differing mechanisms of action are available for treatment of advanced colorectal cancer: fluorouracil, irinotecan, and oxaliplatin. In this study, we compared the activity and toxicity of three different two-drug combinations in patients with metastatic colorectal cancer who had not been treated previously for advanced disease. Patients were concurrently randomly assigned to receive irinotecan and bolus fluorouracil plus leucovorin (IFL, control combination), oxaliplatin and infused fluorouracil plus leucovorin (FOLFOX), or irinotecan and oxaliplatin (IROX). The primary end point was time to progression, with secondary end points of response rate, survival time, and toxicity. A total of 795 patients were randomly assigned between May 1999 and April 2001. A median time to progression of 8.7 months, response rate of 45%, and median survival time of 19.5 months were observed for FOLFOX. These results were significantly superior to those observed for IFL for all end points (6.9 months, 31%, and 15.0 months, respectively) or for IROX (6.5 months, 35%, and 17.4 months, respectively) for time to progression and response. The FOLFOX regimen had significantly lower rates of severe nausea, vomiting, diarrhea, febrile neutropenia, and dehydration. Sensory neuropathy and neutropenia were more common with the regimens containing oxaliplatin. The FOLFOX regimen of oxaliplatin and infused fluorouracil plus leucovorin was active and comparatively safe. It should be considered as a standard therapy for patients with advanced colorectal cancer.

Different doses of bevacizumab in combination with chemotherapy for advanced colorectal cancer: a meta-analysis and Bayesian analysis.

The aim of the present study was to explore the incremental benefit of bevacizumab (Bev) in the treatment of advanced colorectal cancer (CRC) with different doses. A literature search of eight electronic databases (China National Knowledge Infrastructure, Wanfang databases, Chinese Biomedical Database, VIP medicine information, Cochrane Library, MEDLINE, PubMed, and EMBASE) was conducted from database creation to December 2022. Randomized controlled trials (RCTs) that compared Bev at various dosages + chemotherapy (CT) versus placebo (or blank control) + CT were selected. The overall survival (OS), progression-free survival (PFS), overall response rate (ORR; complete response [CR] + partial response [PR]), and grade ≥ 3 adverse events (AEs) were integrated first by pooled analysis. The likelihood of ideal dosage of Bev was then ranked using random effects within Bayesian analysis. Twenty-six RCTs involving 18,261 patients met the inclusion criteria. OS increased significantly after using 5mg (HR: 0.87, 95% CI 0.75 to 1.00) and 10mg dosages of Bev (HR: 0.75, 95% CI 0.66 to 0.85) with CT, but statistical significance was not attained for the 7.5mg dose (HR: 0.95, 95% CI 0.83 to 1.08). A significantly increased in PFS with doses of 5mg (HR: 0.69, 95% CI 0.58 to 0.83), 7.5mg (HR: 0.81, 95% CI 0.66 to 1.00), and 10mg (HR: 0.60, 95% CI 0.53 to 0.68). ORR distinctly increased after 5mg (RR: 1.34, 95% CI 1.15 to 1.55), 7.5mg (RR: 1.25, 95% CI 1.05 to 1.50), and10mg (RR: 2.27, 95% CI 1.82 to 2.84) doses were administered. Grade ≥ 3 AEs increased clearly in 5mg (RR: 1.11, 95% CI 1.04 to 1.20) compared to 7.5mg (RR: 1.05, 95% CI 0.82 to 1.35) and 10mg (RR: 1.15, 95% CI 0.98 to 1.36). Bayesian analysis demonstrated that 10mg Bev obtained the maximum time of OS (HR: 0.75, 95% CrI 0.58 to 0.97; probability rank = 0.05) indirectly compared to 5mg and 7.5mg Bev. Compared with 5mg and 7.5mg Bev, 10mg Bev also holds the longest duration for PFS (HR: 0.59, 95% CrI 0.43 to 0.82; probability rank = 0.00). In terms of ORR, 10mg Bev holds the maximum frequency (RR: 2.02, 95% CrI 1.52 to 2.66; probability rank = 0.98) in comparison to 5mg and 7.5mg Bev clearly. For grade ≥ 3 AEs, 10mg Bev has the maximum incidence (RR: 1.15, 95% CrI 0.95 to 1.40, probability rank = 0.67) in comparison to other doses of Bev. The study suggests that 10mg dose Bev could be more effective in treating advanced CRC in efficacy, but 5mg Bev could be more safer in terms of safety.