Leucovorin and fluorouracil with or without oxaliplatin as first-line treatment in advanced colorectal cancer

Estimating the Survival Impact of Curative-Intent Liver Therapies for Colorectal Cancer Liver Metastases

BACKGROUND

For patients with colorectal cancer liver metastasis (CRCLM), curative-intent liver therapies are associated with improved survival. However, randomized data are lacking, and individual-level retrospective data are limited by selection bias. We aimed to quantify the survival impact of these therapies by analyzing how regional variation in liver therapy rates influence survival outcomes within health service areas (HSA).

PATIENTS AND METHODS

The Surveillance, Epidemiology, and End Results (SEER)-Medicare database (2000-2020) was analyzed for patients aged 66-85 years with liver-isolated CRCLM who underwent curative-intent liver therapy (i.e., hepatectomy, ablation, or transplantation). Rates of resection within HSAs for each year were calculated. A comparison of observed versus expected survival was performed between two eras (era 1: 2002-2004; era 2: 2013-2015) to quantify the impact of changing rates of curative-intent liver therapy on HSA-level survival.

RESULTS

A total of 34,781 patients across 163 HSAs were included. Most patients had synchronous CRCLM (65.8%) and received chemotherapy (63.1%); a minority (10.9%) underwent curative-intent liver therapy (hepatectomy, 74.3%; ablation alone, 24.9%; transplantation 0.8%). A total of 56 (34%) HSAs had the rate of curative-intent liver therapy increase (≥ 5%) across eras, 58 (36%) HSAs had the rate remain constant, and 49 (30%) HSAs experienced a rate decrease (≥ 5%). Each 5% increase in the rate of curative-intent liver therapy was associated with a 1.2% (95% CI 0.4-2.0%) increase in the risk-adjusted survival rate (p = 0.003).

CONCLUSIONS

HSA variation in rates of curative-intent therapy for CRCLM was associated with population-level changes in survival. These data quantify the expected improvements associated with efforts to increase patient access to curative-intent therapies for CRCLM.

Novel exosome-associated LncRNA model predicts colorectal cancer prognosis and drug response

BACKGROUND

Exosomes are extracellular vesicles that carry various biological substances and have potential as functional mediators in cancers. However, little is known about special molecules in colorectal cancer (CRC) exosomes and their immunological functions.

AIMS

Using genomic data from the TCGA-CRC cohort, we constructed a prognostic model based on exosome-related lncRNA for the first time, and the biological role of MIR4713HG in CRC was deeply analyzed.

METHOD

In this study, we downloaded the gene expression data and clinical data of CRC from the TCGA database. The limma package, SVM-REF and univariate Cox analysis were used to screen out core ERG (CERG) in CRC. LASSO and multivariate Cox regression analyses were used to filter out CERG-related LncRNA and construct a risk score. We explored the distribution and expression levels of ERG in immune cell types by scRNA-seq data. xCell was used to calculate the infiltration levels of stromal cells and immune cells in CRC. KM plotter was used for immunotherapy evaluation of core ERG. Next, we further provide colony formation assay, Transwell assay and xenograft models to understand the carcinogenic effect of MIR4713HG.

RESULT

First, 43 differentially expressed ERG and 7 CERG were obtained. We explored the expression and distribution levels of CERG in 9 types of cells by scRNA-seq data. In addition, two key exosome-associated LncRNA (MIR4713HG and ZEB1-AS1) were obtained, and a risk score (EALncRI) was constructed. EALncRI could accurately predict the prognosis of CRC. Based on the EALncRI, we constructed a nomogram that is easy to use in clinical practice, which can more accurately and stably predict the prognosis of CRC patients. Furthermore, EALncRI was significantly correlated with the expression of 5 HLA molecules and 13 immune checkpoint molecules. MIR4713HG showed a good predictive effect in the overall survival of patients with immunotherapy evaluation. Knocking down the expression of MIR4713HG significantly inhibited proliferation and migration, and also impaired subcutaneous tumor growth in nude mice.

CONCLUSION

In this study, a variety of machine learning algorithms were used to construct the EALncRI based on ERG, which can effectively predict the prognosis and distinguish the immune landscape of CRC. More importantly, we conducted an in-depth study on MIR4713HG, which may become an important therapeutic target in CRC.

Systemic Therapy for Metastatic Colon Cancer: New Frontiers

We have made steady gains in improving overall survival in patients with metastatic, unresectable, colon cancer in the last 5 to 10 years. The backbone of systemic treatment for most patients remains combination chemotherapy, but the field is becoming increasingly biomarker driven, with exciting new targeted therapies on the horizon. This review is organized in sections corresponding to currently relevant biomarkers in colon cancer and will summarize first-, second-, and third-line standard of care for metastatic, unresectable, colon cancer. The last section is intended to introduce the reader to promising agents and novel therapeutic strategies currently under investigation.

Toxicity of the FOLFOX-6 regimen, with or without 5-fluorouracil bolus, in metastatic colorectal cancer

OBJECTIVE

Standard treatment of metastatic colorectal cancer includes oxaliplatin and 5-fluorouracil in continuous infusion. Although FOLFOX-6 is the reference combination, it is aggressive and has high toxicity. Variants such as the TTD regimen, which does not include folinic acid or 5-fluorouracil bolus, are used. This study evaluates the toxicity of FOLFOX-6 and TTD in first line treatment for metastatic colorectal cancer and its effectiveness.

METHOD

Retrospective observational study with patients who started treatment with FOLFOX-6 and TTD, for three years. Demographic and clinical data were collected (age, sex, chronic pathologies, molecular profile, laterality, ECOG classification and stage), as well as treatment variables (previous adjuvant chemotherapy, intentionality, number of cycles, duration and pharmacogenetic aspects) and toxicity. Objective response rate and progression-free survival were calculated.

RESULTS

The study included 71 patients, 35 treated with FOLFOX-6 and 36 with TTD. Both groups showed similar overall toxicity profiles. FOLFOX-6 had a higher incidence of neutropenia (46% vs. 8%; p < 0.01) and mucositis (51% vs. 22%; p < 0.013). In addition, there were more treatment delays (40% vs. 11%; p < 0.05) and 5-fluorouracil dose reductions (22% vs. 14%; p < 0.05) in the FOLFOX-6 group. Deaths due to toxicity were only recorded in the FOLFOX-6 group. Effectiveness was similar in both groups.

CONCLUSIONS

The TTD regimen could be a beneficial first-line option for metastatic colorectal cancer, with lower toxicity and effectiveness comparable to FOLFOX-6. It is a safe alternative for elderly or frail patients, suitable for reduced-dose 5-fluorouracil regimen with oxaliplatin.

Sequential Treatment of Metastatic Colorectal Cancer in Taiwan: Real-World Evidence From Regorafenib and Trifluridine/Tipiracil Use

OBJECTIVE

This study aims to evaluate the real-world effectiveness and safety of sequential treatment with regorafenib and trifluridine/tipiracil (FTD-TPI) in patients with metastatic colorectal cancer (mCRC) in Taiwan.

METHODS

Data were obtained from Taiwan's National Health Insurance Research Database (NHIRD) to assess clinical outcomes in mCRC patients who were treated with both drugs in either sequential order from 2016 to 2019. Overall survival (OS) was analyzed using Kaplan-Meier curves and Cox's proportional hazard models, with adjustments made for age, gender, Quan-CCI score, presence of liver metastases, number of metastatic sites, and the use of anti-epidermal growth factor receptor medications. Additionally, age-stratified subgroups and sensitivity analyses were conducted to examine the robustness of our findings.

RESULTS

Five hundred and twenty-eight patients receiving both study drugs were included. The regorafenib/FTD-TPI group demonstrated a longer median OS of 14.1 months compared with 10.2 months in the FTD-TPI/regorafenib group (p = 0.007). The survival benefit for the regorafenib/FTD-TPI sequence remained significant after adjustment (adjusted HR, 1.49; p = 0.002). The mean treatment duration was also longer for regorafenib/FTD-TPI than FTD-TPI/regorafenib (337 vs. 214 days; p < 0.01). No significant difference between the sequential treatment groups was observed in any adverse event of interest. Both subgroup and sensitivity analyses yielded outcomes consistent with the main analysis.

CONCLUSION

The findings indicated that initiating treatment with regorafenib followed by FTD-TPI had superior clinical outcomes compared with the reverse sequence among mCRC patients. This study offers real-world evidence for clinical decision-making and treatment optimization.

Folate-Associated Gene Expression in Primary Tumors Is Associated With Tumor Response and Progression-Free Survival of Patients With Metastatic Colorectal Cancer Undergoing 5-FU/Leucovorin-Based Combination Chemotherapy

BACKGROUND

5-Fluorouracil (5-FU) and the Folate Leucovorin (LV) form the chemotherapy backbone for metastatic colorectal cancer (mCRC). Tumoral expression of specific folate-associated genes is associated with the risk of recurrence in stage III CRC following adjuvant 5-FU/LV (FLV)-based combination chemotherapy according to the Nordic bolus regimen. The aim was to evaluate whether expression of folate-associated genes in Pre-therapeutic tumor samples is associated with outcomes of patients with mCRC undergoing palliative FLV-based combination chemotherapy.

PATIENTS AND METHODS

Patients treated with FLV (n = 113), FLV + oxaliplatin (FLOX, n = 102), or FLV + irinotecan (FLIRI, n = 75) were included. ABCC3, RFC-1, PCFT, MFT, MTHFD2, and TYMS expression was determined by qPCR and related to tumor response and 3-year progression-free survival (PFS). Analyses were conducted on the entire cohort and on subgroups (group 1: stage I-III; group 2: stage IV, at primary surgery). Multivariate Cox proportional hazard models were applied to assess associations between covariates and PFS.

RESULTS

Low TYMS and high MFT expression in group 1, and high ABCC3 expression in group 2 correlated with better PFS (HR 1.37 (1.04-1.82), HR 0.49 (0.30-0.80), and HR 0.74 (0.60-0.93)), respectively. In addition, high MFT expression was associated with better PFS of patients treated with FLIRI (HR 0.47 (0.27-0.81), p = 0.007) whereas high expression of ABCC3 was associated with better PFS of patients treated with FLOX (HR 0.46 (0.23-0.92), p = 0.029).

CONCLUSION

While pretherapeutic tumoral expression of specific folate-associated genes may not serve as a universal predictive marker for FLV-based treatment, it might predict response and outcomes in patients receiving FLOX or FLIRI. Evaluating the impact of gene expression in primary tumors should consider subgrouping of patients by disease stage at diagnosis as well as the applied chemotherapy regimen. Prospective clinical studies on patients with mCRC are warranted to validate these findings.

[Translated article] Toxicity of the FOLFOX-6 regimen, with or without 5-fluorouracil bolus, in metastatic colorectal cancer

OBJECTIVE

Standard treatment of metastatic colorectal cancer includes oxaliplatin and 5-fluorouracil in continuous infusion. Although FOLFOX-6 is the reference combination, it is aggressive and has high toxicity. Variants such as the TTD regimen, which does not include folinic acid or 5-fluorouracil bolus, are used. This study evaluates the toxicity of FOLFOX-6 and TTD in first line treatment for metastatic colorectal cancer and its effectiveness.

METHOD

Retrospective observational study with patients who started treatment with FOLFOX-6 and TTD, for 3 years. Demographic and clinical data were collected (age, sex, chronic pathologies, molecular profile, laterality, Eastern Cooperative Oncology Group classification, and stage), as well as treatment variables (previous adjuvant chemotherapy, intentionality, number of cycles, duration, and pharmacogenetic aspects) and toxicity. Objective response rate and progression-free survival were calculated.

RESULTS

The study included 71 patients, 35 treated with FOLFOX-6, and 36 with TTD. Both groups showed similar overall toxicity profiles. FOLFOX-6 had a higher incidence of neutropenia (46% vs 8%; P < .01) and mucositis (51% vs 22%; P < .013). In addition, there were more treatment delays (40% vs 11%; P < .05) and 5-fluorouracil dose reductions (22% vs 14%; P < .05) in the FOLFOX-6 group. Deaths due to toxicity were only recorded in the FOLFOX-6 group. Effectiveness was similar in both groups.

CONCLUSIONS

The TTD regimen could be a beneficial first-line option for metastatic colorectal cancer, with lower toxicity and effectiveness comparable to FOLFOX-6. It is a safe alternative for elderly or frail patients, suitable for reduced-dose 5-fluorouracil regimen with oxaliplatin.

Chronic myelogenous leukemia secondary to colon cancer: A case report

BACKGROUND

Colon cancer is a common malignancy of the digestive tract. An estimated 1148515 new cases of colon cancer were reported in 2020 worldwide. Chronic myeloid leukemia (CML) is a malignant tumor formed by the clonal proliferation of bone marrow hematopoietic stem cells, with an annual incidence rate of 1-2 cases per 100000 people worldwide. Leukemia can be secondary to solid tumors, and vice versa. Reports on CML secondary malignant tumors account for 8.7% but CML secondary to malignancy is extremely rare. Therapy-related CML is a rare but potentially fatal adverse event of chemotherapy or radiotherapy. Herein, we report a case of CML with colon cancer and discuss this unique patient population. Our findings can provide effective raw data and guidance for the diagnosis of this clinical disease.

CASE SUMMARY

A 61-year-old male patient attended our hospital due to leukocytosis for 5 days. In February 2020, the patient was diagnosed with colon cancer and underwent radical surgery and conventional chemotherapy with a stable condition. He was diagnosis was CML-chronic phase (Sokal score of 0.72) after examination. He was treated with imatinib (400 mg daily). When his conditions improved, the patient was discharged from our hospital and visited the outpatient department for follow-up twice a month.

CONCLUSION

CML in patients with colon cancer is extremely rare. Secondary hematological tumors may be multifactorial, and the exact mechanism is currently unknown. Owing to the slow progression of the disease, patients with CML show no symptoms in the early stage. However, with disease progression, obvious but non-specific symptoms may appear, including fever, anemia, bleeding tendency, and hypertrophy. Therefore, complete blood count monitoring for routine examination is recommended after cancer treatment for early detection of occult hematological tumors.

Histone lactylation enhances GCLC expression and thus promotes chemoresistance of colorectal cancer stem cells through inhibiting ferroptosis

Colorectal cancer stem cells (CCSCs) play a critical role in mediating chemoresistance. Lactylation is a post-translational modification induced by lactate that regulates gene expression. However, whether lactylation affects the chemoresistance of CCSCs remains unknown. Here, we demonstrate that histone lactylation enhances CCSC chemoresistance both in vitro and in vivo. Furthermore, our findings showed that p300 catalyzes the lactylation of histone H4 at K12, whereas HDAC1 facilitates its delactylation in CCSCs. Notably, lactylation at H4K12 (H4K12la) upregulates GCLC expression and inhibits ferroptosis in CCSCs, and the inhibition of p300 or LDHA decreases H4K12la levels, thereby increasing the chemosensitivity of CCSCs. Additionally, the GCLC inhibitor BSO promotes ferroptosis and sensitizes CCSCs to oxaliplatin. Taken together, these findings suggest that histone lactylation upregulates GCLC to inhibit ferroptosis signaling, thus enhancing CCSC chemoresistance. These findings provide new insights into the relationship between cellular metabolism and chemoresistance and suggest potential therapeutic strategies targeting p300, LDHA, and GCLC. We showed that histones H4K12 lactylation promoted chemoresistance in CSCs. p300 catalyzes the lactylation of histone H4 at K12, HDAC1 inhibits the histone lactylation at the same site. H4K12la in CSCs regulates the expression of the ferroptosis-related gene GCLC, thereby inhibiting ferroptosis and leading to chemoresistance. Targeting the p300, LDHA, or GCLC may be overcome tumor chemoresistance.

The Role and Mechanism of Innate Immune Regulation in Overcoming Oxaliplatin Resistance and Enhancing Anti-Tumor Efficacy in Colorectal Cancer

Background/Objectives: The reversal effect of cGAMP, as a STING pathway regulator, on oxaliplatin resistance in colorectal cancer was investigated, and its mechanism was proposed. Methods: The efficacy and mechanism of the cGAMP and oxaliplatin combination for oxaliplatin-resistant colorectal cancer through a nude mouse tumor model were investigated and analyzed, and a western blot analysis of tumors was applied. Results: The reversal effect of cGAMP on oxaliplatin resistance in colorectal cancer was investigated, and its mechanism was proposed. After OXA treatment, the IC50 values of HCT116 and HCT116/L cells were 9.04 μmol/L and 47.04 μmol/L, respectively. In nude mouse tumor models, the combination of cGAMP and oxaliplatin significantly reversed the resistance of oxaliplatin to primary drug-resistant HCT116/L colorectal cancer, and the tumor inhibition rate increased from 8% (oxaliplatin alone) to 60% (combination). In the HCT116 nude mouse transplanted tumor model, the combined treatment of cGAMP and oxaliplatin also showed a more significant tumor inhibition effect than oxaliplatin alone, and the tumor inhibition rate increased by 39%, indicating that cGAMP had a considerable improvement effect on oxaliplatin acquired resistance. These results fully demonstrated the synergistic effect of cGAMP and oxaliplatin. Western blot results showed that cGAMP enhanced the sensitivity of oxaliplatin-resistant tumor cells by down-regulating the expression of p-PI3K and p-AKT and up-regulating the expression of p53 protein. Conclusions: cGAMP, as an immunomodulator against oxaliplatin resistance, shows a potential application prospect in treating oxaliplatin-resistant colorectal cancer.

A Systematic Review of Disappearing Colorectal Liver Metastases: Resection or No Resection?

Background: Colorectal cancer is the second most common type of cancer and a leading cause of cancer-related deaths worldwide. Approximately 15% of the patients with colorectal cancer will already have liver metastases (CRLMs) at diagnosis. Luckily, the advances in chemotherapy regimens during the past few decades have led to increased rates of disease regression that could even render an originally unresectable disease resectable. In certain patients with CRLMs, the hepatic lesions are missing on preoperative imaging after neoadjuvant chemotherapy. These patients can undergo surgery with or without resection of the sites of the disappearing liver metastases (DLMs). In this systematic review, we assess the recurrence rate of the DLMs that were left unresected as well as the complete pathologic response of those resected. Methods: A literature search was conducted in PubMed for studies including patients with CRLMs who received neoadjuvant chemotherapy and had DLMs in preoperative imaging. Two independent reviewers completed the search according to the PRISMA checklist. Results: Three hundred and twenty-six patients with 1134 DLMs were included in our review. A total of 47 out of 480 DLMs (72.29%) that were removed had viable tumor cells in postoperative histology. One hundred and forty-five tumors could not be identified intraoperatively and were removed based on previous imaging, with thirty (20.69%) of them presenting viable cancer cells. Four hundred and sixty-five lesions could not be identified and were left in place. Of them, 152 (32.69%) developed local recurrence within 5 years. Of note, 34 DLMs could not be categorized as viable or non-viable tumors. Finally, DLMs that were identifiable intraoperatively had a higher possibility of viable tumors compared to non-identifiable ones (72.29% vs. 20.69%, respectively). Conclusions: Disappearing liver metastases that are left unresected have an increased possibility of recurrence. Patients receiving neoadjuvant treatment for CRLMs may have better survival chances after resecting all the DLM sites, either identifiable intraoperatively or not.

Expert consensus on the optimal management of BRAFV600E-mutant metastatic colorectal cancer in the Asia-Pacific region

The burden of colorectal cancer (CRC) is high in the Asia-Pacific region, and several countries in this region have among the highest and/or fastest growing rates of CRC in the world. A significant proportion of patients will present with or develop metastatic CRC (mCRC), and BRAFV600E-mutant mCRC represents a particularly aggressive phenotype that is less responsive to standard chemotherapies. In light of recent therapeutic advances, an Asia-Pacific expert consensus panel was convened to develop evidence-based recommendations for the diagnosis, treatment, and management of patients with BRAFV600E-mutant mCRC. The expert panel comprised nine medical oncologists from Australia, Hong Kong, Singapore, and Taiwan (the authors), who met to review current literature and develop eight consensus statements that describe the optimal management of BRAFV600E-mutant mCRC in the Asia-Pacific region. As agreed by the expert panel, the consensus statements recommend molecular testing at diagnosis to guide individualized treatment decisions, propose optimal treatment pathways according to microsatellite stability status, advocate for more frequent monitoring of BRAFV600E-mutant mCRC, and discuss local treatment strategies for oligometastatic disease. Together, these expert consensus statements are intended to optimize treatment and improve outcomes for patients with BRAFV600E-mutant mCRC in the Asia-Pacific region.

Effect of systemic FOLFOXIRI plus bevacizumab treatment of colorectal peritoneal metastasis on local and systemic immune cells

AIM

The immune system plays a crucial role in the outcome of colorectal cancer. Systemic chemotherapies modulate the immune cell composition. Little is known about these changes in peritoneal metastasized colorectal cancer. Thus, we aimed to characterize local and systemic immune cells in the course of systemic chemotherapy.

METHODS

We included in total 20 patients with peritoneal metastasized colorectal cancer in our exploratory study. Initially, we investigated the peripheral blood cell distributions before and after systemic chemotherapy in a set of 11 retrospectively collected samples. Then, a prospective clinical cohort was set up to evaluate local and systemic immune cell distribution in detail (n = 9). Tumor tissue, peritoneal fluid, and peripheral blood were collected. The main immune cell subtypes were characterized using flow cytometry and immunohistochemistry, respectively.

RESULTS

Neutrophils and the neutrophil-to-lymphocyte ratio significantly declined in response to systemic chemotherapy while circulating T cells increased (CD8+P = .015, CD4+P = .041). In peritoneal fluid, we observed a decrease of CD25+/FOXP3+/CD4+ regulatory T cells (P = .049) without loss of their ability to produce interferon gamma. T-cell infiltration in the tumor microenvironment showed a considerable variability between patients. However, the number of tumor-infiltrating CD8+ lymphocytes was not significantly changed by the application of systemic chemotherapy. Neither tumor cells nor lymphocytes or macrophages showed noteworthy expression of PD1 or PD-L1.

CONCLUSION

Our data show that immune cell distribution after systemic chemotherapy changes in peripheral blood. Interestingly, in peritoneal fluid only the inhibitory Treg population decreased and local T cells within peritoneal metastases remain unaffected. These data indicate little to no effect of systemic chemotherapy on the local immune system, supporting the need for new therapeutic options.

Digestive cancers: mechanisms, therapeutics and management

Cancers of the digestive system are major contributors to global cancer-associated morbidity and mortality, accounting for 35% of annual cases of cancer deaths. The etiologies, molecular features, and therapeutic management of these cancer entities are highly heterogeneous and complex. Over the last decade, genomic and functional studies have provided unprecedented insights into the biology of digestive cancers, identifying genetic drivers of tumor progression and key interaction points of tumor cells with the immune system. This knowledge is continuously translated into novel treatment concepts and targets, which are dynamically reshaping the therapeutic landscape of these tumors. In this review, we provide a concise overview of the etiology and molecular pathology of the six most common cancers of the digestive system, including esophageal, gastric, biliary tract, pancreatic, hepatocellular, and colorectal cancers. We comprehensively describe the current stage-dependent pharmacological management of these malignancies, including chemo-, targeted, and immunotherapy. For each cancer entity, we provide an overview of recent therapeutic advancements and research progress. Finally, we describe how novel insights into tumor heterogeneity and immune evasion deepen our understanding of therapy resistance and provide an outlook on innovative therapeutic strategies that will shape the future management of digestive cancers, including CAR-T cell therapy, novel antibody-drug conjugates and targeted therapies.

Combination with oxaliplatin improves abscopal effect of oncolytic virotherapy through reorganization of intratumoral macrophages

Intratumoral administration is a widely used method for oncolytic virotherapy, as it enables immediate access of virus particles to the target tumor and potentially lead to the suppression of untreated distant tumors via in situ vaccination. However, because the injection volume and concentration of the virus solution are physically limited, the dose level cannot be increased. Additionally, efficacy in distant tumors needs improvement to prolong patient survival. Here, we demonstrate the benefit of oxaliplatin, with detailed mechanisms revealed through transcriptome analysis, which may provide a solution for the crucial deficiencies of oncolytic virotherapy. In virus-injected tumors, oxaliplatin improved virus retention through suppression of type I interferons. In distant virus-naive tumors, oxaliplatin induced alterations in the intratumoral macrophage characteristics, leading to the chemotaxis and recruitment of activated T cells and subsequently inducing an inflammatory state in the non-injected tumors. Our findings can be a trigger to change the therapeutic paradigm of oncolytic virotherapy for patients with systemic metastases.

The effect of lifestyle interventions on sarcopenia in advanced colorectal cancer: A systematic review

INTRODUCTION

Sarcopenia is a common syndrome in older patients with advanced colorectal cancer that is worsened during standard-of-care chemotherapy and is associated with increased chemotherapy toxicity, impaired quality of life, and poorer survival independent of cancer stage or chemotherapy response. Physical activity and nutrition interventions have been shown to support muscle mass in patients recovering from treatment for early-stage colorectal cancer. The aim of this present review was to evaluate the effect of physical activity and nutritional interventions on sarcopenia in patients with advanced colorectal cancer.

MATERIALS AND METHODS

We performed a systematic literature review of studies investigating the impact of physical activity and nutritional interventions on muscle mass in patients with advanced colorectal cancer. Relevant key words were searched in appropriate databases through December 2022. Review procedures were performed in line with guidelines from the Cochrane Handbook for systematic reviews and Synthesis Without Meta-analysis (SWiM) guidelines.

RESULTS

Twelve studies were identified with 1461 participants of which 587 had advanced colorectal cancer. Eight studies were randomised controlled trials (RCTs). Only two studies exclusively reported on the population with advanced colorectal cancer. Physical activity and nutritional interventions explored were heterogenous. Studies reporting an improvement in muscle mass utilised protein supplementation (one study), moderate intensity aerobic exercise (one study), and assisted resistance training (two studies). However, only a small number of participants with advanced colorectal cancer were included in these studies. Risk of bias was moderate to high for most studies. Recruitment to physical activity interventions was often low although adherence to supervised interventions was high. Physical activity and nutritional interventions across studies were safe.

DISCUSSION

A small number of studies with limited sample size and moderate-to-high risk of bias suggest that assisted resistance training and supported protein intake improve muscle mass in participants with cancer. However, there is currently sparse evidence for the effect of physical activity and nutritional interventions on sarcopenia in the setting of advanced and incurable colorectal cancer. Given the impact of sarcopenia in this population, further research in this area is warranted.

Factors Influencing the Duration of Maintenance Therapy in Metastatic Colorectal Cancer

BACKGROUND/OBJECTIVES

Metastatic colorectal cancer (mCRC) is mainly treated with 5-Fluoro-Uracil (5-FU), Oxaliplatin and Irinotecan chemotherapies and anti-Epidermal Growth Factor Receptor (EGFR) or anti-Vascular Endothelial Growth Factor (VEGF) targeted therapies. Due to chemotherapy-related toxicity, patients receive induction treatment to achieve tumour response followed by maintenance therapy with less cytotoxic molecules or a chemotherapy-free interval to reduce chemotherapy-related toxicity. In this study, the aim was to determine the patient, cancer and treatment factors that influence the duration of maintenance therapy (DMT).

METHODS

We collected retrospective data on a cohort of 133 patients treated at the Centre Georges François Leclerc (CGFL) cancer centre in Dijon between March 2014 and June 2022. Patients had unresectable or potentially resectable diseases. They received first-line induction treatment with chemotherapy and/or targeted therapy and maintenance treatment, defined as the interruption of at least one chemotherapy agent.

RESULTS

In the multivariate analysis, age (HR: 1.02, 95% CI 1.00-1.04, p = 0.031), N2 nodal status (HR: 1.78, 95% CI 1.09-2.89, p = 0.021) and the presence of peritoneal metastases (HR: 2.05, 95% CI 1.25-3.36, p = 0.004), as well as baseline carcino-embryonic antigen (CEA) level (HR: 1.10, 95% CI 1.00-1.20, p = 0.052), were significantly associated to poor DMT. Local treatment of liver metastases also significantly reduced the DMT (HR: 0.49, 95% CI 0.28-0.86, p = 0.013). In our cohort, induction triplet chemotherapy significantly increased the CEA delta (70% vs. 44%, p = 0.047) compared to doublet chemotherapy and led to a higher rate of liver surgery (40% vs. 21%, p = 0.014) and a trend for a higher rate of local treatment of metastases (62% vs. 45%, p = 0.059).

CONCLUSIONS

Duration of maintenance therapy is determined by the initial patient and colorectal cancer characteristics. However, it is significantly increased by local treatment of liver metastases. By reducing the tumour burden, a triplet induction chemotherapy regimen increases the rate of liver metastase resection.

Sweeten the pill: Multi-faceted polysaccharide-based carriers for colorectal cancer treatment

Colorectal cancer (CRC) ranks as the second deadliest cancer globally and the third most common malignant tumor. While surgery remains the primary treatment for CRC, alternative therapies such as chemotherapy, molecular targeted therapy, and immunotherapy are also commonly used. The significant side effects and toxicity of conventional drugs drive the search for novel targeted therapies, including the design of advanced drug delivery systems. Polysaccharide-based biopolymers, with their low toxicity, non-immunogenic behavior, synergistic interactions with other biopolymers, and tissue and cell compatibility, emerge as excellent drug carriers for this application. This review aims to provide an in-depth overview of recent advancements in developing polysaccharide-based biopolymeric carriers for anticancer compounds in the treatment of CRC. We highlight the multifunctional nature of polysaccharides, showcasing their potential as standalone drug carriers or as integral components of intelligent robotic devices for biomedical therapeutic applications. In addition to exploring the opportunities for using carbohydrate polymers in CRC treatment, we address the challenges and failures that may limit their applicability in biomedical research, as well as summarize the recent preclinical and clinical trials, resulting in several commercialization attempts. This comprehensive overview critically summarizes the potential of polysaccharide-based biomaterials in CRC treatment.

Broussoflavonol F exhibited anti-proliferative and anti-angiogenesis effects in colon cancer via modulation of the HER2-RAS-MEK-ERK pathway

BACKGROUND

A prenylated flavonoid, broussoflavonol F (BFF), was isolated from Macaranga genus with cytotoxicities against various cancer cells, though its underlying mechanisms have not been fully elucidated.

HYPOTHESIS

This study aimed to investigate the anti-tumor and anti-angiogenesis activities of BFF and its underlying mechanisms in colon cancer.

METHOD

In the in vitro study, the cytotoxic effects of BFF in human colon cancer HCT-116 and LoVo cells were examined using MTT assay, BrdU assay and colony formation assay. The anti-proliferative effects of BFF in these cells were assessed via cell apoptosis and cell cycle analysis using flow cytometry. The anti-angiogenesis effects of BFF in human endothelial HEMC-1 cells were also detected using scratch wound healing assay and tube formation assay. While the in vivo effects of BFF in colon cancer were further examined in zebrafish embryos and HCT116 tumor-bearing mice. The underlying mechanisms of BFF were predicted using network pharmacology analysis, and Western blotting was performed to validate both in vitro and in vivo results.

RESULTS

BFF exhibited cytotoxicities on 5 colon cancer cell lines, as well as anti-proliferative activities via inducing apoptosis and cell cycle arrest at the G0/G1 phase in HCT116 and LoVo cells. BFF at 1.25-5 µM also suppressed cell proliferation in these two colon cancer cell lines by downregulating HER2, RAS, p-BRAF, p-MEK and p-Erk protein expressions. In addition, BFF at 2.5-5 µM could significantly decrease the length of subintestinal vessels of zebrafish embryos through decreasing mRNA expressions of NRP1a, PDGFba, PDGFRb, KDR, FLT1 and VEGRaa. Besides, BFF exhibited anti-angiogenesis activity via inhibiting cell proliferation, motility and tube formation in HMEC-1 cells. Furthermore, intraperitoneal administration of BFF (10 mg/kg) suppressed tumor growth and decreased the expression of tumor proliferation marker Ki-67 and angiogenesis marker CD31 in the tumor tissues in HCT116 tumor-bearing mice. BFF treatment could also significantly decrease expressions of RAS, p-BRAF, p-MEK and p-Erk in the tumor section, which are consistent with the in vitro results.

CONCLUSIONS

This study revealed the anti-tumor and anti-angiogenesis effects of BFF in colon cancer. This is the first report of the in vitro and in vivo anti-proliferative activity of BFF in colon cancer through regulating the HER2-RAS-MEK-ERK pathway. These findings further support the research development of BFF as an anti-cancer agent in colon cancer.

More subtle microsatellite instability better predicts fluorouracil insensitivity in colorectal cancer patients

Microsatellite instability (MSI) is now widely used as an indispensable biomarker. However, the relationship between MSI-H (high) and defective DNA mismatch repair (MMR) is not as straightforward as has been expected. Genome-edited cells carrying Lynch syndrome mutations do not exhibit drastic MSI typical in MSI-H (i.e. Type B) but more subtle MSI (i.e. Type A). In this study, we explored a connection between Type A MSI and 5-fluorouracil (5-FU) resistance in colorectal cancer patients. Using our precision and high-resolution MSI assay technique, tumour microsatellites were analysed in 30 colorectal cancer patients treated with FOLFOX or CAPOX. Among 30 tumours, eleven (37%) were judged as Type A MSI-positive. In Type A MSI+ tumours, the patient response to fluoropyrimidine and oxaliplatin was significantly poor (Fisher's exact test, p = 0.021). Accordingly, median PFS and OS were significantly poor in Type A+ patients (log-rank test, p < 0.001/p = 0.009). Type A MSI was an independent predictor of patient prognosis in this pilot cohort (Cox regression analysis, p = 0.003). Thus, more subtle Type A MSI better predicts fluoropyrimidine insensitivity in colorectal cancer patients, which may shed light on a hitherto overlooked connection between the MSI phenotypes and drug resistance in human cancer.

Review of Options to Traditional HIPEC for Prevention and Treatment of Peritoneal Metastases

Cytoreductive surgery with HIPEC has definite application to the management of selected patients with peritoneal metastases. Patients who profit most have a complete cytoreductive surgery. Higher-grade tumors such as colorectal cancer, gastric cancer, and ovarian malignancy are benefited by CRS and HIPEC only under limited circumstances. High-grade tumor invades subperitoneal lymphatics where HIPEC is not effective. Options to traditional HIPEC for treatment of invasive intraabdominal malignancies with peritoneal metastases must be explored.

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.

An RNA damage response network mediates the lethality of 5-FU in colorectal cancer

5-fluorouracil (5-FU), a major anti-cancer therapeutic, is believed to function primarily by inhibiting thymidylate synthase, depleting deoxythymidine triphosphate (dTTP), and causing DNA damage. Here, we show that clinical combinations of 5-FU with oxaliplatin or irinotecan show no synergy in human colorectal cancer (CRC) trials and sub-additive killing in CRC cell lines. Using selective 5-FU metabolites, phospho- and ubiquitin proteomics, and primary human CRC organoids, we demonstrate that 5-FU-mediated CRC cell killing primarily involves an RNA damage response during ribosome biogenesis, causing lysosomal degradation of damaged rRNAs and proteasomal degradation of ubiquitinated ribosomal proteins. Tumor types clinically responsive to 5-FU treatment show upregulated rRNA biogenesis while 5-FU clinically non-responsive tumor types do not, instead showing greater sensitivity to 5-FU's DNA damage effects. Finally, we show that treatments upregulating ribosome biogenesis, including KDM2A inhibition, promote RNA-dependent cell killing by 5-FU, demonstrating the potential for combinatorial targeting of this ribosomal RNA damage response for improved cancer therapy.

MAPK Signaling-Mediated RFNG Phosphorylation and Nuclear Translocation Restrain Oxaliplatin-Induced Apoptosis and Ferroptosis

Chemotherapy resistance remains a major challenge in the treatment of colorectal cancer (CRC). Therefore, it is crucial to develop novel strategies to sensitize cancer cells to chemotherapy. Here, the fringe family is screened to determine their contribution to chemotherapy resistance in CRC. It is found that RFNG depletion significantly sensitizes cancer cells to oxaliplatin treatment. Mechanistically, chemotherapy-activated MAPK signaling induces ERK to phosphorylate RFNG Ser255 residue. Phosphorylated RFNG S255 (pS255) interacts with the nuclear importin proteins KPNA1/importin-α1 and KPNB1/importin-β1, leading to its translocation into the nucleus where it targets p53 and inhibits its phosphorylation by competitively inhibiting the binding of CHK2 to p53. Consequently, the expression of CDKN1A is decreased and that of SLC7A11 is increased, leading to the inhibition of apoptosis and ferroptosis. In contrast, phosphor-deficient RFNG S225A mutant showed increased apoptosis and ferroptosis, and exhibited a notable response to oxaliplatin chemotherapy both in vitro and in vivo. It is further revealed that patients with low RFNG pS255 exhibited significant sensitivity to oxaliplatin in a patient-derived xenograft (PDX) model. These findings highlight the crosstalk between the MAPK and p53 signaling pathways through RFNG, which mediates oxaliplatin resistance in CRC. Additionally, this study provides guidance for oxaliplatin treatment of CRC patients.

Third-line treatment and beyond in metastatic colorectal cancer: What do we have and what can we expect?

Colorectal cancer remains the third most common cancer worldwide and the second cause of cancer-related death. Treatment advances and precision oncological medicine for these tumours have been stalled in comparison to those for other common tumours such as lung and breast cancer. However, the recent publication of the SUNLIGHT trial results with the trifluridine/tipiracil (TAS-102)-bevacizumab combination and the irruption of new molecular targets with guided treatments have opened new possibilities in third-line metastatic colorectal cancer management. Anti-EGFR rechallenge, anti-HER2 targeted therapies or the promising results of Pressurised Intraperitoneal Aerosol Chemotherapy (PIPAC), are some of the available options that may modify what is presumably third-line colorectal treatment. Hereby, we present the evidence of the different treatment options in third-line colorectal cancer and beyond, as well as the possibilities of sequencing them.

Ferroptosis-related oxaliplatin resistance in multiple cancers: Potential roles and therapeutic Implications

Oxaliplatin (OXA)-based therapy is effective in the treatment of multiple cancers. However, primary or acquired OXA resistance remains an emerging challenge for its clinical application. Ferroptosis is an iron-dependent mode of cell death that has been demonstrated to play an essential role in the chemoresistance of many drugs, including OXA. In particular, dysregulation of SLC7A11-GPX4, one of the major antioxidant systems of ferroptosis, was found in the OXA resistance of colorectal cancer (CRC) and hepatocellular carcinoma (HCC). In addition, Nrf2, the upstream regulator of GPX4 and many other antioxidant factors, is also involved in the OXA resistance of CRC and HCC. Inhibition of SLC7A11-GPX4 or Nrf2 by genetic deletion of pharmaceutical inhibition could significantly reverse OXA resistance. Long noncoding RNA (lncRNA) also participates in chemoresistance and ferroptosis of cancer cells. Specifically, LINC01134 promotes the recruitment of Nrf2 to the promoter of GPX4, thereby exerting transcriptional regulation of GPX4, which eventually increases the OXA sensitivity of HCC through upregulation of ferroptosis. On the other hand, a novel lncRNA DACT3-AS1 sensitizes gastric cancer cells to OXA through miR-181a-5p/sirtuin 1(SIRT1)-mediated ferroptosis. Therapies based on ferroptosis or a combination of OXA and ferroptosis enhancers could provide new therapeutic insights to overcome OXA resistance. In the present review, we present the current understanding of ferroptosis-related OXA resistance, highlight ferroptosis pathogenesis in OXA chemoresistance, and summarize available therapies that target OXA resistance by enhancing ferroptosis.

Colorectal cancer: Recent advances in management and treatment

Colorectal cancer (CRC) is the third most common cancer worldwide, and the second most common cause of cancer-related death. In 2020, the estimated number of deaths due to CRC was approximately 930000, accounting for 10% of all cancer deaths worldwide. Accordingly, there is a vast amount of ongoing research aiming to find new and improved treatment modalities for CRC that can potentially increase survival and decrease overall morbidity and mortality. Current management strategies for CRC include surgical procedures for resectable cases, and radiotherapy, chemotherapy, and immunotherapy, in addition to their combination, for non-resectable tumors. Despite these options, CRC remains incurable in 50% of cases. Nonetheless, significant improvements in research techniques have allowed for treatment approaches for CRC to be frequently updated, leading to the availability of new drugs and therapeutic strategies. This review summarizes the most recent therapeutic approaches for CRC, with special emphasis on new strategies that are currently being studied and have great potential to improve the prognosis and lifespan of patients with CRC.

Decursin Induces G1 Cell Cycle Arrest and Apoptosis through Reactive Oxygen Species-Mediated Endoplasmic Reticulum Stress in Human Colorectal Cancer Cells in In Vitro and Xenograft Models

Decursin, a coumarin isolated from Angelica gigas Nakai, possesses anti-inflammatory and anti-cancer properties. However, the molecular mechanisms underlying its anti-cancer effects against human colorectal cancer (CRC) are unclear. Therefore, this study aimed to evaluate the biological activities of decursin in CRC in vitro and in vivo and to determine its underlying mechanism of action. Decursin exhibited anti-tumor activity in vitro, accompanied by an increase in G1 cell cycle arrest and apoptosis in HCT-116 and HCT-8 CRC cells. Decursin also induced the production of reactive oxygen species (ROS), thereby activating the endoplasmic reticulum (ER) stress apoptotic pathway in CRC cells. Furthermore, the role of ROS in decursin-induced apoptosis was investigated using the antioxidant N-acetyl-L-cysteine. Inhibiting ROS production reversed decursin-induced ER stress. Moreover, decursin significantly suppressed tumor growth in a subcutaneous xenograft mouse model of HCT-116 and HCT-8 CRC cells without causing host toxicity. Decursin also decreased cell proliferation, as documented by Ki-67, and partly increased cleaved caspase 3 expression in tumor tissues by activating ER stress apoptotic pathways. These findings suggest that decursin induces cell cycle arrest and apoptosis in human CRC cells via ROS-mediated ER stress, suggesting that decursin could be a therapeutic agent for CRC.

Lymph node ratio prognosticates overall survival in patients with stage IV colorectal cancer

BACKGROUND

Lymph node ratio (LNR) is suggested to address the shortcomings of using only lymph node yield (LNY) or status in colorectal cancer (CRC) prognosis. This study explores how LNR affects survival in patients with metastatic colorectal cancer (mCRC), seeking to provide clearer insights into its application.

METHODS

This observational cohort study investigated stage IV patients with CRC (1995-2021) who underwent an upfront resection of their primary tumour at Concord Hospital, Sydney. Clinicopathological data were extracted from a prospective database, and LNR was calculated both continuously and dichotomously (LNR of 0 and LNR > 0). The primary endpoint was overall survival (OS). The associations between LNR and various clinicopathological variables were tested using regression analyses. Kaplan-Meier and Cox regression analyses estimated OS in univariate and multivariate survival models.

RESULTS

A total of 464 patients who underwent a primary CRC resection with clear margins (mean age 68.1 years [SD 13.4]; 58.0% M; colon cancer [n = 339,73.1%]) had AJCC stage IV disease. The median LNR was 0.18 (IQR 0.05-0.42) for colon cancer (CC) resections and 0.21 (IQR 0.09-0.47) for rectal cancer (RC) resections. A total of 84 patients had an LNR = 0 (CC = 66 patients; RC = 18 patients). The 5-year OS for the CC cohort was 10.5% (95% CI 8.7-12.3) and 11.5% (95% CI 8.4-14.6) for RC. Increasing LNR demonstrated a decline in OS in both CC (P < 0.001) and RC (P < 0.001). In patients with non-lymphatic dissemination only (LNR = 0 or N0 status), there was better survival compared with those with lymphatic spread (CC aHR1.50 [1.08-2.07;P = 0.02], RC aHR 2.21 [1.16-4.24;P = 0.02]).

CONCLUSIONS

LNR is worthy of consideration in patients with mCRC. An LNR of 0 indicates patients have a better prognosis, underscoring the need for adequate lymphadenectomy to facilitate precise mCRC staging.

DOSAGE study: protocol for a phase III non-inferiority randomised trial investigating dose-reduced chemotherapy for advanced colorectal cancer in older patients

INTRODUCTION

Treating older adults with chemotherapy remains a challenge, given their under-representation in clinical trials and the lack of robust treatment guidelines for this population. Moreover, older patients, especially those with frailty, have an increased risk of developing chemotherapy-related toxicity, resulting in a decreased quality of life (QoL), increased hospitalisations and high healthcare costs. Phase II trials have suggested that upfront dose reduction of chemotherapy can reduce toxicity rates while maintaining efficacy, leading to fewer treatment discontinuations and an improved QoL. The DOSAGE aims to show that upfront dose-reduced chemotherapy in older patients with metastatic colorectal cancer is non-inferior to full-dose treatment in terms of progression-free survival (PFS), with adaption of the treatment plan (monotherapy or doublet chemotherapy) based on expected risk of treatment toxicity.

METHODS AND ANALYSIS

The DOSAGE study is an investigator-initiated phase III, open-label, non-inferiority, randomised controlled trial in patients aged≥70 years with metastatic colorectal cancer eligible for palliative chemotherapy. Based on toxicity risk, assessed using the Geriatric 8 (G8) tool, patients will be stratified to either doublet chemotherapy (fluoropyrimidine with oxaliplatin) or fluoropyrimidine monotherapy. Patients classified as low risk will be randomised between a fluoropyrimidine plus oxaliplatin in either full-dose or with an upfront dose reduction of 25%. Patients classified as high risk will be randomised between fluoropyrimidine monotherapy in either full-dose or with an upfront dose reduction. In the dose-reduced arm, dose escalation after two cycles is allowed. The primary outcome is PFS. Secondary endpoints include grade≥3 toxicity, QoL, physical functioning, number of treatment cycles, dose reductions, hospital admissions, overall survival, cumulative received dosage and cost-effectiveness. Considering a median PFS of 8 months and non-inferiority margin of 8 weeks, we shall include 587 patients. The study will be enrolled in 36 Dutch Hospitals, with enrolment scheduled to start in July 2024. This study will provide new evidence regarding the effect of dose-reduced chemotherapy on survival and treatment outcomes, as well as the use of the G8 to choose between doublet chemotherapy or monotherapy. Results will contribute to a more individualised approach in older patients with metastatic colorectal cancer, potentially leading to improved QoL while maintaining survival benefits.

ETHICS AND DISSEMINATION

This trial has received ethical approval by the ethical committee Leiden Den Haag Delft (P24.018) and will be approved by the Institutional Ethical Committee of the participating institutions. The results will be disseminated in peer-reviewed scientific journals.

TRIAL REGISTRATION NUMBER

NCT06275958.

Journey through the Decades: The Evolution in Treatment and Shared Decision Making for Locally Advanced Rectal Cancer

The management of locally advanced rectal cancer has undergone significant transformations over the decades and optimal treatment approaches continue to evolve. There have been numerous advances in surgery, chemotherapy, and radiation therapy from the first description of the abdominoperineal resection in 1908, timing of chemotherapy and radiation therapy in the late 20th and early 21st century, and most recently, the introduction of organ preservation or nonoperative management in 2004. Alongside these advancements, the concept of shared decision making in medicine has evolved, prompting a focus on patient-centered care. This evolution in practice has been fueled by a growing recognition of the importance of patient autonomy and the alignment of treatment options with patients' values and preferences. With the growing number of possible treatment options, variability in patient counseling exists, highlighting the need for a standardized approach to shared decision making in locally advanced rectal cancer. This narrative review will describe the evolution of treatment options of locally advanced rectal cancer as well as the concept of shared decision making and decision aids, and will introduce a decision aid for patients with locally advanced rectal cancer who have achieved a complete clinical response and are eligible for watch and wait.

Epidermal growth factor receptor antagonists in colorectal cancer: emerging strategies for precision therapy

INTRODUCTION

The global prevalence of colorectal cancer highlights the need to enhance treatment strategies for improved patient outcomes. The pivotal role of epidermal growth factor receptor (EGFR) signaling in regulating cellular processes for this disease pinpoints its value as a therapeutic target, despite the emergence of resistance mechanisms over time.

AREAS COVERED

This review discusses the clinical evidence supporting the use of EGFR inhibitors in molecularly-selected patients based on molecular characteristics (notably BRAF V600E and KRAS G12C) including combination approaches targeting different points in in the signaling pathway, as well as strategies such as EGFR inhibitor rechallenge. The role of HER2 inhibitors and emerging approaches such as bispecific antibodies are also reviewed.

EXPERT OPINION

Recently, inhibitors targeting the KRAS G12C variant have emerged, albeit with modest monotherapy activity compared to other tumor types, emphasizing the influence of histologic origins on the EGFR signaling pathway. Integration of EGFR inhibitors into precision medicine has facilitated tailored therapies addressing resistance mechanisms. Patient selection for EGFR inhibitor rechallenge guided by ctDNA findings is crucial, with ongoing investigations exploring novel combinations to enhance EGFR blockade, highlighting the transformative potential of precision medicine in shaping the future of mCRC treatment toward personalized and targeted approaches.

Isthmin-1 promotes growth and progression of colorectal cancer through the interaction with EGFR and YBX-1

While previous studies have indicated the involvement of Isthmin 1 (ISM1), a secreted protein, in cancer development, the precise mechanisms have remained elusive. In this study, we unveiled that ISM1 is significantly overexpressed in both the blood and tissue samples of colorectal cancer (CRC) patients, correlating with their poor prognosis. Functional experiments demonstrated that enforced ISM1 expression significantly enhances CRC proliferation, migration, invasion and tumor growth. Notably, our investigation reveals an interaction of ISM1 with epidermal growth factor receptor (EGFR), a member of the receptor tyrosine kinase (RTK) family of CRC cells. The binding of ISM1 triggered EGFR activation and initiate downstream signaling pathways. Meanwhile, intracellular ISM1 interacted with Y-box binding protein 1 (YBX1), enhancing its transcriptional regulation on EGFR. Furthermore, our research uncovered the regulation of ISM1 expression by the hypoxia-inducible transcription factor HIF-1α in CRC cells. Mechanistically, we identified HIF-1α as a direct regulator of ISM1, binding to a hypoxia response element on its promoter. This novel mechanism illuminated potential therapeutic targets, offering insights into restraining HIF-1α/ISM1/EGFR-driven CRC progression and metastasis.

Detailed analysis of metastatic colorectal cancer patients who developed cardiotoxicity on another fluoropyrimidine and switched to S-1 treatment (subgroup analysis of the CardioSwitch-study)

BACKGROUND AND PURPOSE

The CardioSwitch-study demonstrated that patients with solid tumors who develop cardiotoxicity on capecitabine or 5-fluorouracil (5-FU) treatment can be safely switched to S-1, an alternative fluoropyrimidine (FP). In light of the European Medicines Agency approval of S-1 in metastatic colorectal cancer (mCRC), this analysis provides more detailed safety and efficacy information, and data regarding metastasectomy and/or local ablative therapy (LAT), on the mCRC patients from the original study.

MATERIALS AND METHODS

This retrospective cohort study was conducted at 12 European centers. The primary endpoint was recurrence of cardiotoxicity after switch. For this analysis, safety data are reported for 78 mCRC patients from the CardioSwitch cohort (N = 200). Detailed efficacy and outcomes data were available for 66 mCRC patients.

RESULTS

Data for the safety of S-1 in mCRC patients were similar to the original CardioSwitch cohort and that expected for FP-based treatment, with no new concerns. Recurrent cardiotoxicity (all grade 1) with S-1-based treatment occurred in 4/78 (5%) mCRC patients; all were able to complete FP treatment. Median progression-free survival from initiation of S-1-based treatment was 9.0 months and median overall survival 26.7 months. Metastasectomy and/or LAT was performed in 33/66 (50%) patients, and S-1 was successfully used in recommended neoadjuvant/conversion or adjuvant-like combination regimens and schedules as for standard FPs.

INTERPRETATION

S-1 is a safe and effective FP alternative when mCRC patients are forced to discontinue 5-FU or capecitabine due to cardiotoxicity and can be safely used in the standard recommended regimens, settings, and schedules.

Metastatic colorectal cancer- third line therapy and beyond

INTRODUCTION

The outcome of patients with metastatic colorectal cancer (mCRC) has improved significantly in the last few decades. Metastatic colorectal cancer is a highly heterogenous cancer. Beyond second line chemotherapy, treatment decisions are often based on molecular testing.

METHOD

In this narrative review, we provide a comprehensive summary of data from key clinical trials and discuss how to integrate these agents into the current treatment landscape of metastatic colorectal cancer.

EXPERT OPINION

In the era of precision medicine, molecular testing plays an increasingly important role in the management of mCRC. Efforts need to be made to target treatment based on molecular test results.

Optimal duration of oxaliplatin-based adjuvant chemotherapy in patients with different risk factors for stage II-III colon cancer: a meta-analysis

BACKGROUND

The duration of oxaliplatin-based chemotherapy in high-risk stage II, low-risk stage III, and high-risk stage III colon cancer (CC) patients is controversial. To reduce the risk of adverse events (AEs) without compromising efficacy while improving chemotherapy compliance is crucial.

METHODS

The authors searched Cochrane, Embase, Pubmed, and Web of Science databases for articles from inception to August 8, 2023, the main outcomes were disease-free survival, overall survival, chemotherapy completion rates, and AE frequency.

RESULTS

Six randomized controlled trials (RCTs) involving 10 332 patients were included. Disease-free survival analysis revealed that only the high-risk stage III CC patients experienced better results with the 6-month FOLFOX regimen when compared with the 3-month regimen [Hazard ratio (HR): 1.32, 95% CI: 1.15-1.51, P <0.0001). Overall survival (OS) analysis revealed that extending the use of FOLFOX and CAPEOX regimens did not provide survival benefits for stage III CC patients (HR: 1.16, 95% CI: 0.9-1.49, and HR: 0.89, 95% CI: 0.67-1.18, P =0.40). The completion rate of the 3-month oxaliplatin-based adjuvant chemotherapy regimen was significantly higher than that of the 6-month regimen [Relative risk (RR): 1.16, 95% CI: 1.06-1.27, P =0.002]. Moreover, the 3-month regimen had significantly lower AE rates than the 6-month regimen (RR: 0.62, 95% CI: 0.57-0.68, P <0.00001), with differences mainly concentrated in grade 3/4 neutropenia (RR: 0.70, 95% CI: 0.59-0.85, P =0.0002), peripheral sensory neuropathy at ≥grade 2 (RR: 0.45, 95% CI: 0.38-0.53, P <0.00001), and hand-foot syndrome at ≥grade 2 (RR: 0.36, 95% CI: 0.17-0.77, P =0.009).

CONCLUSION

The 6-month FOLFOX regimen should only be recommended for high-risk stage III CC, while the 3-month regimen can be recommended for other stages. A 3-month CAPEOX regimen can be recommended for stage II-III CC.

Monoclonal Antibodies for First-Line Treatment of Metastatic Colorectal Cancer

BACKGROUND

In addition to discontinuing treatment at disease progression, cumulative toxicity limitations and genetic mutations play important roles in chemotherapy choice in metastatic colorectal cancer (mCRC). However, in recent years, targeted therapies, such as immune checkpoint inhibitors or monoclonal antibodies (MoAbs), have been used with chemotherapy to improve clinical outcomes in patients with mCRC.

AREAS OF UNCERTAINTY

Approximately 15% of patients with CRC would be eligible for further targeted therapy with immune checkpoint inhibitors based on genetic testing, but most patients with CRC would not qualify, especially Kirsten rat sarcoma wild-type. Therefore, adding MoAb is only an option for most patients until disease progression or unacceptable toxicity occurs. However, the results are not consistent with the combination of MoAb and different chemotherapy bases. In addition, most results from combining MoAb with different chemotherapy bases are not consistent.

DATA SOURCES

This meta-analysis includes published of the PubMed and Embase databases, limited to English literature, and patients were treated with MoAb combination. Randomized control trials conducted published up to May 2021 were considered for inclusion.

THERAPEUTIC ADVANCES

Fluoropyrimidine-based chemotherapy has been the backbone of palliative therapy for mCRC, with demonstrated benefits. This article will review the efficacy and safety of randomized control trials comparing different MoAb with fluoropyrimidine-based chemotherapy as first-line therapy for patients with mCRC, particularly in Kirsten rat sarcoma wild-type.

CONCLUSION

This meta-analysis revealed that MoAb plus chemotherapy has better progression-free survival and objective response rate than chemotherapy alone. However, treatment-related serious adverse events (grade ≥ 3) should be considered, particularly severe rash, diarrhea, and hypertension.

Manganese- and Platinum-Driven Oxidative and Nitrosative Stress in Oxaliplatin-Associated CIPN with Special Reference to Ca4Mn(DPDP)5, MnDPDP and DPDP

Platinum-containing chemotherapeutic drugs are efficacious in many forms of cancer but are dose-restricted by serious side effects, of which peripheral neuropathy induced by oxidative-nitrosative-stress-mediated chain reactions is most disturbing. Recently, hope has been raised regarding the catalytic antioxidants mangafodipir (MnDPDP) and calmangafodipir [Ca4Mn(DPDP)5; PledOx®], which by mimicking mitochondrial manganese superoxide dismutase (MnSOD) may be expected to overcome oxaliplatin-associated chemotherapy-induced peripheral neuropathy (CIPN). Unfortunately, two recent phase III studies (POLAR A and M trials) applying Ca4Mn(DPDP)5 in colorectal cancer (CRC) patients receiving multiple cycles of FOLFOX6 (5-FU + oxaliplatin) failed to demonstrate efficacy. Instead of an anticipated 50% reduction in the incidence of CIPN in patients co-treated with Ca4Mn(DPDP)5, a statistically significant increase of about 50% was seen. The current article deals with confusing differences between early and positive findings with MnDPDP in comparison to the recent findings with Ca4Mn(DPDP)5. The POLAR failure may also reveal important mechanisms behind oxaliplatin-associated CIPN itself. Thus, exacerbated neurotoxicity in patients receiving Ca4Mn(DPDP)5 may be explained by redox interactions between Pt2+ and Mn2+ and subtle oxidative-nitrosative chain reactions. In peripheral sensory nerves, Pt2+ presumably leads to oxidation of the Mn2+ from Ca4Mn(DPDP)5 as well as from Mn2+ in MnSOD and other endogenous sources. Thereafter, Mn3+ may be oxidized by peroxynitrite (ONOO-) into Mn4+, which drives site-specific nitration of tyrosine (Tyr) 34 in the MnSOD enzyme. Conformational changes of MnSOD then lead to the closure of the superoxide (O2•-) access channel. A similar metal-driven nitration of Tyr74 in cytochrome c will cause an irreversible disruption of electron transport. Altogether, these events may uncover important steps in the mechanism behind Pt2+-associated CIPN. There is little doubt that the efficacy of MnDPDP and its therapeutic improved counterpart Ca4Mn(DPDP)5 mainly depends on their MnSOD-mimetic activity when it comes to their potential use as rescue medicines during, e.g., acute myocardial infarction. However, pharmacokinetic considerations suggest that the efficacy of MnDPDP on Pt2+-associated neurotoxicity depends on another action of this drug. Electron paramagnetic resonance (EPR) studies have demonstrated that Pt2+ outcompetes Mn2+ and endogenous Zn2+ in binding to fodipir (DPDP), hence suggesting that the previously reported protective efficacy of MnDPDP against CIPN is a result of chelation and elimination of Pt2+ by DPDP, which in turn suggests that Mn2+ is unnecessary for efficacy when it comes to oxaliplatin-associated CIPN.

Albendazole inhibits colon cancer progression and therapy resistance by targeting ubiquitin ligase RNF20

BACKGROUND

The repurposing of FDA-approved drugs for anti-cancer therapies is appealing due to their established safety profiles and pharmacokinetic properties and can be quickly moved into clinical trials. Cancer progression and resistance to conventional chemotherapy remain the key hurdles in improving the clinical management of colon cancer patients and associated mortality.

METHODS

High-throughput screening (HTS) was performed using an annotated library of 1,600 FDA-approved drugs to identify drugs with strong anti-CRC properties. The candidate drug exhibiting most promising inhibitory effects in in-vitro studies was tested for its efficacy using in-vivo models of CRC progression and chemoresistance and patient derived organoids (PTDOs).

RESULTS

Albendazole, an anti-helminth drug, demonstrated the strongest inhibitory effects on the tumorigenic potentials of CRC cells, xenograft tumor growth and organoids from mice. Also, albendazole sensitized the chemoresistant CRC cells to 5-fluorouracil (5-FU) and oxaliplatin suggesting potential to treat chemoresistant CRC. Mechanistically, Albendazole treatment modulated the expression of RNF20, to promote apoptosis in CRC cells by delaying the G2/M phase and suppressing anti-apoptotic-Bcl2 family transcription.

CONCLUSIONS

Albendazole, an FDA approved drug, carries strong therapeutic potential to treat colon cancers which are aggressive and potentially resistant to conventional chemotherapeutic agents. Our findings also lay the groundwork for further clinical testing.

Emerging therapeutic approaches for peritoneal metastases from gastrointestinal cancers

Peritoneal metastases from gastrointestinal malignancies present difficult management decisions, with options consisting primarily of systemic chemotherapy or major surgery with or without hyperthermic intraperitoneal chemotherapy. Current research is investigating expanding therapeutic modalities, and the aim of this review is to provide an overview of the existing and emerging therapies for the peritoneal metastases from gastrointestinal cancers, primarily through the recent literature (2015 and newer). These include the current data with systemic therapy and cytoreduction with hyperthermic intraperitoneal or pressurized intraperitoneal aerosol chemotherapy, as well as novel promising modalities under investigation, including dominating oncolytic viral therapy and adoptive cellular, biologic, and bacteria therapy, or nanotechnology. The novel diverse strategies, although preliminary and preclinical in murine models, individually and collectively contribute to the treatment of peritoneal metastases, offering hope for improved outcomes and quality of life. We foresee that these evolving treatment approaches will facilitate the transfer of knowledge and data among studies and advance discovery of new drugs and optimized treatments for patients with peritoneal metastases.

Recent Advances in Therapeutic Strategies to Improve Colorectal Cancer Treatment

Colorectal cancer (CRC) is the second-leading cause of cancer-related mortality worldwide. CRC mortality results almost exclusively from metastatic disease (mCRC) for which systemic chemotherapy is often a preferred therapeutic option. Biomarker-based stratification of mCRC enables the use of precision therapy based on individual tumor mutational profiles. Activating mutations in the RAS/RAF/MAPK pathway downstream of EGFR signaling have, until recently, limited the use of EGFR-targeted therapies for mCRC; however, the development of anti-RAS and anti-RAF therapies together with improved strategies to limit compensatory signaling pathways is resulting in improved survival rates in several highly lethal mCRC sub-types (e.g., BRAF-mutant). The use of fluoropyrimidine (FP)-based chemotherapy regimens to treat mCRC continues to evolve contributing to improved long-term survival. Future advances in chemotherapy for mCRC will need to position development relative to the advances made in precision oncology.

Liver Transplantation for Colorectal Liver Metastases

Colorectal cancer is one of the most common malignancies worldwide. Approximately half of the patients diagnosed will develop colorectal liver metastases (CRLM). Liver resection has a 50% 5-year survival; however, only a fourth of cases are resectable. Unresectable CRLM has poor prognosis despite improved systemic and local ablative treatments. Liver transplantation (LT) has demonstrated a survival benefit in initial prospective clinical trials. Current use of LT for CRLM is limited to several randomized trials and high-performing centers. Improving patient selection criteria and perioperative management, LT will likely become an important part of the multidisciplinary approach to managing the metastatic disease.

Glucagon Enhances Chemotherapy Efficacy By Inhibition of Tumor Vessels in Colorectal Cancer

Chemotherapy is widely used to treat colorectal cancer (CRC). Despite its substantial benefits, the development of drug resistance and adverse effects remain challenging. This study aimed to elucidate a novel role of glucagon in anti-cancer therapy. In a series of in vitro experiments, glucagon inhibited cell migration and tube formation in both endothelial and tumor cells. In vivo studies demonstrated decreased tumor blood vessels and fewer pseudo-vessels in mice treated with glucagon. The combination of glucagon and chemotherapy exhibited enhanced tumor inhibition. Mechanistic studies demonstrated that glucagon increased the permeability of blood vessels, leading to a pronounced disruption of vessel morphology. Signaling pathway analysis identified a VEGF/VEGFR-dependent mechanism whereby glucagon attenuated angiogenesis through its receptor. Clinical data analysis revealed a positive correlation between elevated glucagon expression and chemotherapy response. This is the first study to reveal a role for glucagon in inhibiting angiogenesis and vascular mimicry. Additionally, the delivery of glucagon-encapsulated PEGylated liposomes to tumor-bearing mice amplified the inhibition of angiogenesis and vascular mimicry, consequently reinforcing chemotherapy efficacy. Collectively, the findings demonstrate the role of glucagon in inhibiting tumor vessel network and suggest the potential utility of glucagon as a promising predictive marker for patients with CRC receiving chemotherapy.

A Randomized Phase III Study of Arfolitixorin versus Leucovorin with 5-Fluorouracil, Oxaliplatin, and Bevacizumab for First-Line Treatment of Metastatic Colorectal Cancer: The AGENT Trial

PURPOSE

Suboptimal treatment outcomes with 5-fluorouracil (5-FU)/folate, the standard of care for metastatic colorectal cancer (mCRC), have generated interest in optimizing the folate. Arfolitixorin ([6R]-5,10-methylene-tetrahydrofolate) is an immediately active folate and may improve outcomes over the existing standard of care (leucovorin).

EXPERIMENTAL DESIGN

AGENT was a randomized, phase III study (NCT03750786). Patients with mCRC were randomized to arfolitixorin (120 mg/m2 given as two intravenous bolus doses of 60 mg/m2) or leucovorin (400 mg/m2 given as a single intravenous infusion) plus 5-FU, oxaliplatin, and bevacizumab. Assessments were performed every 8 weeks. The primary endpoint was the superiority of arfolitixorin for overall response rate (ORR).

RESULTS

Between February 2019 and April 2021, 490 patients were randomized (245 to each arm). After a median follow-up of 266 days, the primary endpoint of superiority for ORR was not achieved (48.2% for arfolitixorin vs. 49.4% for leucovorin, Psuperiority = 0.57). Outcomes were not achieved for median progression-free survival (PFS; 12.8 and 11.6 months, P = 0.38), median duration of response (12.2 and 12.9 months, P = 0.40), and median overall survival (23.8 and 28.0 months, P = 0.78). The proportion of patients with an adverse event of grade ≥3 severity was similar between arms (68.7% and 67.2%, respectively), as was quality of life. BRAF mutations and MTHFD2 expression were both associated with a lower PFS with arfolitixorin.

CONCLUSIONS

The study failed to demonstrate clinical benefit of arfolitixorin (120 mg/m2) over leucovorin. However, it provides some useful insights from the first-line treatment setting, including the effect of gene expression on outcomes.

SIGNIFICANCE

This phase III study compared arfolitixorin, a direct-acting folate, with leucovorin in FOLFOX plus bevacizumab in mCRC. Arfolitixorin (120 mg/m2) did not improve the ORR, potentially indicating a suboptimal dose.

Multiple Protein Biomarkers and Different Treatment Strategies for Colorectal Carcinoma: A Comprehensive Prospective

In this review, we emphasized important biomarkers, pathogenesis, and newly developed therapeutic approaches in the treatment of colorectal cancer (CRC). This includes a complete description of small-molecule inhibitors, phytopharmaceuticals with antiproliferative potential, monoclonal antibodies for targeted therapy, vaccinations as immunotherapeutic agents, and many innovative strategies to intervene in the interaction of oncogenic proteins. Many factors combine to determine the clinical behavior of colorectal cancer and it is still difficult to comprehend the molecular causes of a person's vulnerability to CRC. It is also challenging to identify the causes of the tumor's onset, progression, and responsiveness or resistance to antitumor treatment. Current recommendations for targeted medications are being updated by guidelines throughout the world in light of the growing number of high-quality clinical studies. So, being concerned about the aforementioned aspects, we have tried to present a summarized pathogenic view, including a brief description of biomarkers and an update of compounds with their underlying mechanisms that are currently under various stages of clinical testing. This will help to identify gaps or shortfalls that can be addressed in upcoming colorectal cancer research.

2022 Peritoneal Surface Oncology Group International Consensus on HIPEC Regimens for Peritoneal Malignancies: Colorectal Cancer

BACKGROUND

Selected patients with peritoneal metastases of colorectal cancer (PM-CRC) can benefit from potentially curative cytoreductive surgery (CRS) ± hyperthermic intraperitoneal chemotherapy (HIPEC), with a median overall survival (OS) of more than 40 months.

OBJECTIVE

The aims of this evidence-based consensus were to define the indications for HIPEC, to select the preferred HIPEC regimens, and to define research priorities regarding the use of HIPEC for PM-CRC.

METHODS

The consensus steering committee elaborated and formulated pertinent clinical questions according to the PICO (patient, intervention, comparator, outcome) method and assessed the evidence according to the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) framework. Standardized evidence tables were presented to an international expert panel to reach a consensus (4-point, weak and strong positive/negative) on HIPEC regimens and research priorities through a two-round Delphi process. The consensus was defined as ≥ 50% agreement for the 4-point consensus grading or ≥ 70% for either of the two combinations.

RESULTS

Evidence was weak or very weak for 9/10 clinical questions. In total, 70/90 eligible panelists replied to both Delphi rounds (78%), with a consensus for 10/10 questions on HIPEC regimens. There was strong negative consensus concerning the short duration, high-dose oxaliplatin (OX) protocol (55.7%), and a weak positive vote (53.8-64.3%) in favor of mitomycin-C (MMC)-based HIPEC (preferred choice: Dutch protocol: 35 mg/m2, 90 min, three fractions), both for primary cytoreduction and recurrence. Determining the role of HIPEC after CRS was considered the most important research question, regarded as essential by 85.7% of the panelists. Furthermore, over 90% of experts suggest performing HIPEC after primary and secondary CRS for recurrence > 1 year after the index surgery.

CONCLUSIONS

Based on the available evidence, despite the negative results of PRODIGE 7, HIPEC could be conditionally recommended to patients with PM-CRC after CRS. While more preclinical and clinical data are eagerly awaited to harmonize the procedure further, the MMC-based Dutch protocol remains the preferred regimen after primary and secondary CRS.

Beta-Hydroxybutyrate Augments Oxaliplatin-Induced Cytotoxicity by Altering Energy Metabolism in Colorectal Cancer Organoids

Deregulation of cellular metabolism has recently emerged as a notable cancer characteristic. This reprogramming of key metabolic pathways supports tumor growth. Targeting cancer metabolism demonstrates the potential for managing colorectal cancer. Beta-hydroxybutyrate (BOHB) acts as an acetyl-CoA source for the tricarboxylic acid (TCA) cycle, possibly redirecting energy metabolic pathways towards the TCA cycle that could enhance sensitivity to oxaliplatin, through the generation of reactive oxygen species (ROS). This study explores the potential of BOHB to enhance oxaliplatin's cytotoxic effect by altering the energy metabolism in colorectal cancer. The study employed advanced in vitro organoid technology, which successfully emulates in vivo physiology. The combination treatment efficacy of BOHB and oxaliplatin was evaluated via cell viability assay. The levels of key proteins involved in energy metabolism, apoptotic pathways, DNA damage markers, and histone acetylation were analyzed via Western Blot. ROS levels were evaluated via flow cytometer. Non-toxic doses of BOHB with oxaliplatin significantly amplified cytotoxicity in colorectal cancer organoids. Treatment with BOHB and/or melatonin resulted in significantly decreased lactate dehydrogenase A and increased mitochondrial carrier protein 2 levels, indicating inhibited aerobic glycolysis and an increased oxidative phosphorylation rate. This metabolic shift induced apoptotic cell death mediated by oxaliplatin, owing to high levels of ROS. Melatonin counteracted this effect by protecting cancer cells from high oxidative stress conditions. BOHB may enhance the efficacy of chemotherapeutics with a similar mechanism of action to oxaliplatin in colorectal cancer treatment. These innovative combinations could improve treatment outcomes for colorectal cancer patients.

Selecting Optimal First-Line Treatment for Microsatellite Stable and Non-Mutated RAS/BRAF Metastatic Colorectal Cancer

OPINION STATEMENT

Standard frontline treatment of metastatic colorectal cancer (CRC) is cytotoxic chemotherapy plus a biologic agent such as an anti-EGFR monoclonal antibody (cetuximab or panitumumab) or anti-VEGF antibody (bevacizumab). Predictive biomarkers include mismatch repair (MMR) status, and RAS and BRAF mutation status; and important factors in treatment selection include primary tumor location, intent of therapy, and potential toxicity, as well as patient age, comorbidities, and patient preference. To date, single-, double-, or triple-agent cytotoxic chemotherapy all have important roles in appropriately selected patients, with the addition of anti-VEGF or anti-EGFR antibody therapy based on the relevant predictive biomarker. Data indicate that patients with proficient MMR, RAS/BRAF wt mCRC are candidates for an anti-EGFR antibody plus doublet chemotherapy if they have a left-sided primary tumor, or for anti-VEGF (bevacizumab) plus doublet or triplet chemotherapy if they have a right-sided primary tumor. Future studies may provide more predictive biomarkers to further personalize therapy for this heterogeneous disease.