Efficacy of Regorafenib in Metastatic Colorectal Cancer: A Multi-institutional Retrospective Study

Evaluating the Pharmacokinetics and Pharmacodynamics of Chemotherapeutics within a Spatial SILAC-Labeled Spheroid Model System

Tumors have considerable cellular heterogeneity that is impossible to explore with simple cell cultures. Spheroid cultures contain pathophysiological and chemical gradients similar to in vivo tumors and show complex responses to therapeutics, similar to a tumor. Using pulsed isotopic labels, we demonstrate the pronounced differential response of the proteome to the drug Regorafenib, a multikinase inhibitor, in HCT 116 spheroids. Regorafenib treatment of outer spheroids inhibits proteins involved in critical pathways such as mTOR signaling, extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) signaling, and colorectal cancer metastasis signaling, resulting in decreased proliferation and cellular apoptosis. By contrast, analysis of the treated core cells shows upregulation of MAPK1 and KRAS, possibly implicating drug resistance within these late apoptotic cells. Thus, pulsed isotopic labeling enables evaluation of the distinct proteomic responses for cells residing in the different chemical microenvironments of the spheroid. This platform promises great utility in assisting researchers' predictions of pharmacodynamic therapeutic responses within complex tumors.

Targeted Therapies in Colorectal Cancer: Recent Advances in Biomarkers, Landmark Trials, and Future Perspectives

In 2022, approximately 600,000 cancer deaths were expected; more than 50,000 of those deaths would be from colorectal cancer (CRC). The CRC mortality rate in the US has decreased in recent decades, with a 51% drop between 1976 and 2014. This drop is attributed, in part, to the tremendous therapeutic improvements, especially after the 2000s, in addition to increased social awareness regarding risk factors and diagnostic improvement. Five-fluorouracil, irinotecan, capecitabine, and later oxaliplatin were the mainstays of mCRC treatment from the 1960s to 2002. Since then, more than a dozen drugs have been approved for the disease, betting on a new chapter in medicine, precision oncology, which uses patient and tumor characteristics to guide the therapeutic choice. Thus, this review will summarize the current literature on targeted therapies, highlighting the molecular biomarkers involved and their pathways.

Targeting Myc-driven stress addiction in colorectal cancer

MYC is a proto-oncogene that encodes a powerful regulator of transcription and cellular programs essential for normal development, as well as the growth and survival of various types of cancer cells. MYC rearrangement and amplification is a common cause of hematologic malignancies. In epithelial cancers such as colorectal cancer, genetic alterations in MYC are rare. Activation of Wnt, ERK/MAPK, and PI3K/mTOR pathways dramatically increases Myc levels through enhanced transcription, translation, and protein stability. Elevated Myc promotes stress adaptation, metabolic reprogramming, and immune evasion to drive cancer development and therapeutic resistance through broad changes in transcriptional and translational landscapes. Despite intense interest and effort, Myc remains a difficult drug target. Deregulation of Myc and its targets has profound effects that vary depending on the type of cancer and the context. Here, we summarize recent advances in the mechanistic understanding of Myc-driven oncogenesis centered around mRNA translation and proteostress. Promising strategies and agents under development to target Myc are also discussed with a focus on colorectal cancer.

Eficácia e Segurança de Regorafenibe em Pacientes com Características de Bom Prognóstico no Tratamento do Câncer Colorretal Metastático: Análise de Subgrupo do Estudo CORRECT

Introdução: O câncer colorretal (CCR) e o segundo mais incidente e, quando metastático, apresenta taxa de sobrevida de 14% em cinco anos. Regorafenibe e um inibidor de tirosina-quinase (ITQ) aprovado para CCR metastático (CCRm) com aumento comprovado de sobrevida global (SG). Objetivo: Explorar resultados de eficácia e segurança de regorafenibe em pacientes com CCRm e características de bom prognostico (CBP). Método: Analise de subgrupo do estudo CORRECT, com participantes divididos de acordo com CBP, seguindo os critérios: Eastern Cooperative Oncology Group (ECOG) 0, tempo de doença metastática maior que 18 meses, até três sítios metastáticos e ausência de metástase hepática. Eficácia comparada com teste de log-rank estratificado e hazad ratios (HR) calculados com o modelo de Cox. Resultados: Dos 760 participantes randomizados, 292 (34,5%) apresentavam CBP; 185 (63,4%) receberam regorafenibe; 107 (35,6%), placebo. Para o grupo CBP, a mediana SG foi 10,9 meses (IC95%:8,8-12,3) para regorafenibe e 7,3 meses (IC95%:5,6-9,1) para placebo, com 39% de redução no risco de morte (HR 0,61; IC95%:0,43-0,88; p=0,0069). A mediana de sobrevida livre de progressão (SLP) foi de 3,5 meses (IC95%:3,0-3,9) versus 1,8 mês (IC95%:1,7-1,8) respectivamente, com 61% de redução no risco de progressão da doença ou morte (HR 0,39; IC95%:0,30-0,52; p<0,0001). Os eventos adversos graus 3 e 4 foram mais frequentes para regorafenibe. Após definição de valor basal para escores de qualidade de vida (EQ-5D), estes descaíram menos para regorafenibe comparados com placebo (0,687 versus 0,592) com diferença significativa de 0,09. Conclusão: Pacientes com CBP que receberam regorafenibe melhoraram SG e SLP com menor deterioração da qualidade de vida comparado com placebo.

Outcomes of Patients with Metastatic Colorectal Cancer Treated with Trifluridine/Tipiracil beyond the Second Line: A Multicenter Retrospective Study from Saudi Arabia

Background

The outcome of patients with refractory metastatic colorectal cancer (mCRC) treated with trifluridine/tipiracil (FTD/TPI) beyond the second-line has not been studied in Saudi Arabia. Therefore, this multicenter retrospective analysis was conducted to evaluate the efficacy of FTD/TPI.

Methods

This multicenter retrospective analysis included five centers in Saudi Arabia. FTD/TPI was administered to all the patients beyond the oxaliplatin- and irinotecan-based chemotherapy regimens. The electronic medical records were reviewed, and progression-free survival (PFS) and overall survival (OS) were determined.

Results

The study included 100 patients with a mean age of 55.4 ± 11.8 years. The overall response to FTD/TPI was 4%. The median PFS was 4 months (95% confidence interval (CI) 3.487–4.513), and the median OS was 11 months (95% CI, 9.226–12.771). In a Cox regression analysis of the independent predictors for PFS, advanced stage of the disease (P = 0.037; HR, 2.614; and CI, 1.102–7.524), presence of lymph node metastasis (P = 0.018; HR, 3.664; and 95% CI, 1.187–8.650), and >2 metastatic sites (P = 0.020; HR, 1.723; and 95% CI, 1.089–2.727) were independent factors predicting disease progression. The Cox regression analysis confirmed that age ≥ 55 years (P = 0.046; HR, 1.667; and 95%, 1.097–3.100), advanced disease stage (P = 0.044; HR, 1.283; and 95% CI, 1.035–2.940), prior use of adjuvant chemotherapy (P = 0.037; HR, 0.892; and 95% CI, 0.481–0.994), liver metastasis (P = 0.025; HR, 2.015; and 95% CI, 1.091–3.720), >2 metastatic sites (P = 0.038; HR, 1.248; and 95% CI, 1.036–1.846), development of neutropenia after receiving first cycle of FTD/TPI (P = 0.042; HR, 1.505; and 95% CI, 1.064–2.167), and increased number of FTD/TPI cycles (P = 0.002; HR, 0.769; and 95% CI, 0.664–0.891) were independent variables for OS.

Conclusion

Treatment with FTD/TPI is feasible and effective in daily clinical practice in Saudi Arabian patients. The risk of progression increased with advanced disease stage, lymph node metastasis, bone metastasis, and metastasis to >2 sites. Age ≥ 55 years, advanced disease stage, liver metastasis, metastasis to >2 sites, neutropenia after the first cycle of FTD/TPI, and increased number of FTD/TPI cycles were independent factors predicting mortality.

The prognostic role of neutrophil-to-lymphocyte ratio and C-reactive protein in metastatic colorectal cancer using regorafenib: a systematic review and meta-analysis

Background

The application of regorafenib has changed the landscape of subsequent-line treatment in metastatic colorectal cancer (mCRC). Baseline neutrophil-to-lymphocyte ratio (NLR) and C-reactive protein (CRP), as two of the most common inflammatory factors, are suggested to be potential prognostic factors for mCRC patients treated with regorafenib, but the results are conflicting. In this study, we conducted a meta-analysis to evaluate the prognostic role of NLR and CRP in mCRC patients treated with regorafenib.

Methods

We searched online databases such as Embase, PubMed, and the Cochrane library up to April 2022, without language limitation, to identify clinical studies evaluating the prognostic role of NLR or CRP in regorafenib treated mCRC patients. The main endpoints were hazard ratio (HR) of overall survival (OS) and progression-free survival (PFS). The associations between NLR, CRP, and the above endpoints were extracted. Review Manager 5.4 was used to conduct the combined analysis. The Newcastle-Ottawa Scale (NOS) was applied for assessing the quality of included studies. Heterogeneity was detected by chi-square-based Q test and I² statistic, and publication bias was evaluated by funnel plot asymmetry and Egger's test.

Results

Eight studies involving 1,287 cases were included, with 5 reporting survival outcomes based on NLR level and 4 reporting survival according to CRP level. The results of meta-analysis showed that the calculated HR of OS for subsequent-line regorafenib in mCRC patients with high versus low NLR was 2.52 [I²=52%, 95% confidence interval (CI): 1.75-3.64; P<0.00001]. The combined HR of PFS with high versus low baseline NLR was 2.11 (I²=12%, 95% CI: 1.80-2.48; P<0.00001). For patients with a high level of CRP, the OS was significantly shorter when compared with patients with a low level of CRP (I²=0%, HR =1.88; 95% CI: 1.55-2.29; P<0.00001).

Conclusions

High level of NLR could be associated with OS in mCRC patients treated with regorafenib. It is suggested that the impact of regorafenib on OS may vary according to the baseline NLR.

The Angiogenic Balance and Its Implications in Cancer and Cardiovascular Diseases: An Overview

Angiogenesis is the process of developing new blood vessels from pre-existing ones. This review summarizes the main features of physiological and pathological angiogenesis and those of angiogenesis activation and inhibition. In healthy adults, angiogenesis is absent apart from its involvement in female reproductive functions and tissue regeneration. Angiogenesis is a complex process regulated by the action of specific activators and inhibitors. In certain diseases, modulating the angiogenic balance can be a therapeutic route, either by inhibiting angiogenesis (for example in the case of tumor angiogenesis), or by trying to activate the process of new blood vessels formation, which is the goal in case of cardiac or peripheral ischemia.

Molecular Subtyping Combined with Biological Pathway Analyses to Study Regorafenib Response in Clinically Relevant Mouse Models of Colorectal Cancer

PURPOSE

Regorafenib (REG) is approved for the treatment of metastatic colorectal cancer, but has modest survival benefit and associated toxicities. Robust predictive/early response biomarkers to aid patient stratification are outstanding. We have exploited biological pathway analyses in a patient-derived xenograft (PDX) trial to study REG response mechanisms and elucidate putative biomarkers.

EXPERIMENTAL DESIGN

Molecularly subtyped PDXs were annotated for REG response. Subtyping was based on gene expression (CMS, consensus molecular subtype) and copy-number alteration (CNA). Baseline tumor vascularization, apoptosis, and proliferation signatures were studied to identify predictive biomarkers within subtypes. Phospho-proteomic analysis was used to identify novel classifiers. Supervised RNA sequencing analysis was performed on PDXs that progressed, or did not progress, following REG treatment.

RESULTS

Improved REG response was observed in CMS4, although intra-subtype response was variable. Tumor vascularity did not correlate with outcome. In CMS4 tumors, reduced proliferation and higher sensitivity to apoptosis at baseline correlated with response. Reverse phase protein array (RPPA) analysis revealed 4 phospho-proteomic clusters, one of which was enriched with non-progressor models. A classification decision tree trained on RPPA- and CMS-based assignments discriminated non-progressors from progressors with 92% overall accuracy (97% sensitivity, 67% specificity). Supervised RNA sequencing revealed that higher basal EPHA2 expression is associated with REG resistance.

CONCLUSIONS

Subtype classification systems represent canonical "termini a quo" (starting points) to support REG biomarker identification, and provide a platform to identify resistance mechanisms and novel contexts of vulnerability. Incorporating functional characterization of biological systems may optimize the biomarker identification process for multitargeted kinase inhibitors.

Efficacy and Safety of Regorafenib Monotherapy among Patients with Previously Treated Metastatic Colorectal Cancer in a Chinese Population: A Real-World Exploratory Study

Background

Present study was condeucted to investigate the efficacy and safety of regorafenib for patients with previously treated metastatic colorectal cancer (mCRC) in a Chinese population and the prognostic implications of adverse reactions.

Methods

This retrospective study a total of 96 consecutive patients with mCRC who had failed standard chemotherapy regimens from June 2017 to December 2020. Patients received regorafenib at an initial dosage of 160 mg or 120 mg. The primary end point was progression-free survival (PFS), and secondary end points objective response rate (ORR), disease-control rate (DCR), overall survival (OS), safety, and associations between prognosis and adverse-reaction status.

Results

There were three patients with partial response, 49 with stable disease, and 44 with progressive disease. Consequently, the ORR and DCR of the 96 patients were 3.1% (95% CI 0.6%–8.9%) and 54.2% (95% CI 43.7–64.4%), respectively. Prognosis results showed that median PFS of the 96 patients was 2.5 (95% CI 1.98–3.02) months and median OS 9.8 (95% CI 7.02–12.59) months. Additionally, the most frequent adverse reactions during regorafenib treatment were hand–foot syndrome (HFS; 52.1%), hypertension (38.5%), and fatigue (33.3%). Interestingly, the relevance of prognosis to adverse-reaction status exhibited that median PFS of patients with HFS and patients without HFS was 3.3 months and 2.0 months, respectively (P=0.013). Similarly, median PFS of patients with hypertension and without hypertension was 3.6 months and 2.2 months, respectively (P=0.023).

Conclusion

Potential clinical benefit of regorafenib monotherapy was observed for patients with mCRC who had failed standard chemotherapy regimens. Hypertension and HFS induced by regorafenib therapy could be used as valuable biomarkers to predict the prognosis of regorafenib.

Association of albumin-bilirubin score in patients with colorectal cancer receiving later-line chemotherapy with regorafenib

BACKGROUND

Regorafenib is recognized as a later-line standard treatment in patients with metastatic colorectal cancer (mCRC). In this study, we examined the association of the albumin-bilirubin (ALBI) score in patients with mCRC receiving later-line chemotherapy with regorafenib.

PATIENTS AND METHODS

We retrospectively analyzed data from patients with mCRC treated with regorafenib in a later line between January 2013 and December 2019. Patients were divided into a Normal-ALBI group (ALBI grade 1) and a High-ALBI group (ALBI grades 2 and 3). Primary endpoint was median overall survival (OS) and secondary endpoints were median time to treatment failure (TTF) and incidence of adverse events (AEs).

RESULTS

Data from 60 patients were analyzed (Normal-ALBI group: 32 patients and High-ALBI group: 28 patients). Median OS [10.23 vs. 3.70 months, hazard ratio (HR): 1.79, 95% confidence interval (CI) 1.02-3.13, p = 0.041] and median TTF (2.27 vs. 1.78 months, HR: 1.78, 95%CI 1.02-3.09, p = 0.042) were significantly longer in the Normal-ALBI group than High-ALBI group. On Cox proportional hazard analysis, ALBI score was significantly correlated with OS. The incidence of liver dysfunction (grade ≥ 2) was significantly higher in the High-ALBI than the Normal-ALBI group (42.9% vs. 15.6%, p = 0.041), whereas other AEs were comparable between the two groups.

CONCLUSION

ALBI was strongly associated with the prognosis of patients with mCRC treated with regorafenib and with the occurrence of liver-related adverse events. These findings may imply that patients with a high ALBI score should not be treated with regorafenib.

Management of colorectal cancer in the era of COVID-19: Challenges and suggestions

The Coronavirus (COVID-19) pandemic had a huge impact on all sectors around the world. In particular, the healthcare system has been subject to an enormous pressure that has surpassed its ability in many instances. Additionally, the pandemic has called for a review of our daily medical practices, including our approach to colorectal cancer management where treatment puts patients at high risk of virus exposure. Given their higher median age, patients are at an increased risk for severe symptoms and complications in cases of infection, especially in the setting of immunosuppression. Therefore, a review of the routine colorectal cancer practices is needed to minimize risk of exposure. Oncologists should weigh risk of exposure versus the patient's oncologic benefits when approaching management. In addition, treatment protocols should be modified to minimize hospital visits and admissions while maintaining the same treatment efficacy. In this review, we will focus on challenges that colorectal cancer patients face during the pandemic, while highlighting the priority in each case. We will also discuss the evidence for potential modifications to existing treatment plans that could reduce infectious exposure without compromising care. Finally, we will discuss the impact of the socio-economic difficulties faced by Lebanese patients due to a poor economy toppled by an unexpected pandemic.

Dendritic cell vaccine therapy for colorectal cancer

Colorectal cancer (CRC) remains a leading cause of cancer-related deaths in the United States despite an array of available treatment options. Current standard-of-care interventions for this malignancy include surgical resection, chemotherapy, and targeted therapies depending on the disease stage. Specifically, infusion of anti-vascular endothelial growth factor agents in combination with chemotherapy was an important development in improving the survival of patients with advanced colorectal cancer, while also helping give rise to other forms of anti-angiogenic therapies. Yet, one approach by which tumor angiogenesis may be further disrupted is through the administration of a dendritic cell (DC) vaccine targeting tumor-derived blood vessels, leading to cytotoxic immune responses that decrease tumor growth and synergize with other systemic therapies. Early generations of such vaccines exhibited protection against various forms of cancer in pre-clinical models, but clinical results have historically been disappointing. Sipuleucel-T (Provenge®) was the first, and to-date, only dendritic cell-based therapy to receive FDA approval after significantly increasing overall survival in prostate cancer patients. The unparalleled success of Sipuleucel-T has helped revitalize the clinical development of dendritic cell vaccines, which will be examined in this review. We also highlight the promise of these vaccines to instill anti-angiogenic immunity for individuals with advanced colorectal cancer.

Simulating the human colorectal cancer microenvironment in 3D tumor-stroma co-cultures in vitro and in vivo

The tumor microenvironment (TME) plays a significant role in cancer progression and thus modeling it will advance our understanding of cancer growth dynamics and response to therapies. Most in vitro models are not exposed to intact body physiology, and at the same time, fail to recapitulate the extensive features of the tumor stroma. Conversely, animal models do not accurately capture the human tumor architecture. We address these deficiencies with biofabricated colorectal cancer (CRC) tissue equivalents, which are built to replicate architectural features of biopsied CRC tissue. Our data shows that tumor-stroma co-cultures consisting of aligned extracellular matrix (ECM) fibers and ordered micro-architecture induced an epithelial phenotype in CRC cells while disordered ECM drove a mesenchymal phenotype, similar to well and poorly differentiated tumors, respectively. Importantly, co-cultures studied in vitro, and upon implantation in mice, revealed similar tumor growth dynamics and retention of architectural features for 28 days. Altogether, these results are the first demonstration of replicating human tumor ECM architecture in ex vivo and in vivo cultures.

Population pharmacokinetics of regorafenib in solid tumours: Exposure in clinical practice considering enterohepatic circulation and food intake

Aim

Regorafenib is an oral multikinase inhibitor with clinical efficacy in a range of advanced solid tumours. A population pharmacokinetic (PK) model was developed to evaluate the variability of the PK of regorafenib and its pharmacologically active metabolites M‐2 and M‐5 in solid tumours.

Methods

The model was initially developed using densely sampled phase 1 data and information on food intake to incorporate enterohepatic circulation (EHC) that was identified to considerably contribute to the PK of regorafenib. This was then applied to sparsely sampled data from four phase 3 studies in patients with advanced solid tumours. The need for exact food intake data to estimate individual drug exposure was evaluated.

Results

By incorporating EHC, the model adequately described the PK profiles of regorafenib, M‐2 and M‐5 after single and multiple doses in patients from phase 1 studies. Individual exposure in phase 3 studies was adequately described based on assumptions on the time and frequency of food intake, although exact food intake data are recommended to improve the estimation. Covariate analysis identified sex and body mass index (BMI) as impacting exposure to regorafenib, and sex as strongly impacting exposure to M‐2 and M‐5 (also influenced by the BMI effect on parent regorafenib in the joint model developed); however, these factors accounted for a small portion of the overall variability in exposure.

Conclusions

The adequate description of regorafenib PK after multiple dosing requires the incorporation of EHC. Neither single nor combined covariates predicted exposures that would warrant a priori regorafenib dose adjustment.

Drug-Drug Interactions of Irinotecan, 5-Fluorouracil, Folinic Acid and Oxaliplatin and Its Activity in Colorectal Carcinoma Treatment

The combination of folinic acid, 5-fluorouracil, oxaliplatin and/or irinotecan (FOLFOXIRI) is the standard of care for metastatic colorectal cancer (CRC). This strategy inhibits tumor growth but provokes drug resistance and serious side effects. We aimed to improve FOLFOXIRI by optimization of the dosing and the sequence of drug administration. We employed an orthogonal array composite design and linear regression analysis to obtain cell line-specific drug combinations for four CRC cell lines (DLD1, SW620, HCT116, LS174T). Our results confirmed the synergy between folinic acid and 5-fluorouracil and additivity, or even antagonism, between the other drugs of the combination. The drug combination administered at clinical doses resulted in significantly higher antagonistic interactions compared to the low-dose optimized drug combination (ODC). We found that the concomitant administration of the optimized drug combination (ODC) was comparatively active to sequential administration. However, the administration of oxaliplatin or the active metabolite of irinotecan seemed to sensitize the cells to the combination of folinic acid and 5-fluorouracil. ODCs were similarly active in non-cancerous cells as compared to the clinically used doses, indicating a lack of reduction of side effects. Interestingly, ODCs were inactive in CRC cells chronically pretreated with FOLFOXIRI, suggesting the occurrence of resistance. We were unable to improve FOLFOXIRI in terms of efficacy or specificity. Improvement of CRC treatment should come from the optimization of targeted drugs and immunotherapy strategies.