Complete response with fluorouracil and irinotecan with a BRAFV600E and EGFR inhibitor in BRAF-mutated metastatic colorectal cancer: a case report

Preparation, Characterization, and Antiangiogenic Evaluation of a Novel 5-Fluorouracil Derivative Solid Lipid Nanoparticle with a Hen's Egg Chorioallantoic Membrane Assay and Wound Healing Response in HaCaT Keratinocytes

5-Fluorouracil is a heterocyclic aromatic organic compound, and it is commonly used as a chemotherapeutic agent in many cancers. The present goal is to analyze and characterize the physicochemical and biological properties of a new therapeutic formulation of 5-FUD-Gal under simulated chronic wound and oxidative stress conditions. After synthesis of a new 5-fluorouracil derivative, preparation and characterization of the formulation were carried out. The antiangiogenic effect, wound healing, and oxidative stress responses were conducted with a HET-CAM assay and in vitro cell culture technique. The results initially demonstrated that 5-FUD-Gal synthesized by a series of reactions and the SLN formulation were prepared successfully. A strong cell protective effect above 98% cell viability was detected at 20 μM at 48 h. The wound closure of the HaCaT scratch assay was calculated to be 90.12 and 98.98% at 10 and 20 μM concentrations, respectively, at 48 h. Moreover, the strongest effect of 5-FUD-Gal-F was observed at 20 μM concentration on chicken embryos. This study provides novel insights that a new derivative of semisynthetic 5-FUD-Gal-F can be further evaluated as a therapeutic chemical compound in cancer disease.

Triple-Regimen of Vemurafenib, Irinotecan, and Cetuximab for the Treatment of BRAFV600E-Mutant CRC: A Case Report and Review

Mutation of the BRAF proto-oncogene is found in approximately 10% of colorectal cancers (CRC), with much of the mutation conferred by a V600E mutation. Unlike other CRC subtypes, BRAF-mutant CRC have had relatively limited response to conventional therapies and overall poor survival. We present the case of a 75-year-old man with severe nonischemic cardiomyopathy on a LifeVest who was found to have a transverse colonic mass with widespread hepatic metastatic disease and was subsequently found to have BRAF^V600E-mutant CRC (MSI High/dMMR). After a failed therapy with FOLFOX and pembrolizumab, the patient was started on a regimen of vemurafenib, irinotecan, and cetuximab (VIC) based on the SWOG 1406 trial which had shown improved progression-free survival and response rate for the treatment of BRAF^V600E-mutant metastatic CRC. After 40 cycles of VIC, the patient attained complete response and is in remission off chemotherapy with significant improvement. This case highlights the effectiveness of the triple-regimen of vemurafenib, irinotecan, and cetuximab as a treatment option for BRAF^V600E-mutant CRC, which is a treatment regimen based on the SWOG 1406 trial, and also demonstrates the synergistic role of BRAF^V600E inhibitors and EGFR inhibitors in the treatment of BRAF^V600E-mutant CRC.

The Role of Dynamic ctDNA Monitoring During Combination Therapies of BRAF V600E-Mutated Metastatic Colorectal Cancer: A Case Report

BACKGROUND

BRAF V600E mutation represents a group of colorectal carcinoma with poor prognosis. Although treatment strategies have been recommended after clinical investigations, the progression-free survival is short and unsatisfying.

CASE PRESENTATION

Here, we present the case of a 28-year-old male diagnosed with ascending colon adenocarcinoma with multiple liver metastases. Treatment with FOLFIRI plus cetuximab and vemurafenib achieved partial response, following which the patient received conversion surgery with clear resection margin. After disease recurrence, he received combination treatment of nivolumab and regorafenib. Until August 2020, the patient achieved a partial response with more than 12 months progression-free survival. Circulating tumor DNA (ctDNA) was monitored during the patient's treatment. His ctDNA fractions exhibited significant elevation two months before disease progression. As a comparison, the tumor markers were not elevated until the patient was confirmed PD through CT imaging.

CONCLUSION

This case exemplifies how liquid biopsy and ctDNA sequencing can aid in real-time molecular characterization of tumors.

Colorectal liver metastases: Current management and future perspectives

The liver is the commonest site of metastatic disease for patients with colorectal cancer, with at least 25% developing colorectal liver metastases (CRLM) during the course of their illness. The management of CRLM has evolved into a complex field requiring input from experienced members of a multi-disciplinary team involving radiology (cross sectional, nuclear medicine and interventional), Oncology, Liver surgery, Colorectal surgery, and Histopathology. Patient management is based on assessment of sophisticated clinical, radiological and biomarker information. Despite incomplete evidence in this very heterogeneous patient group, maximising resection of CRLM using all available techniques remains a key objective and provides the best chance of long-term survival and cure. To this end, liver resection is maximised by the use of downsizing chemotherapy, optimisation of liver remnant by portal vein embolization, associating liver partition and portal vein ligation for staged hepatectomy, and combining resection with ablation, in the context of improvements in the functional assessment of the future remnant liver. Liver resection may safely be carried out laparoscopically or open, and synchronously with, or before, colorectal surgery in selected patients. For unresectable patients, treatment options including systemic chemotherapy, targeted biological agents, intra-arterial infusion or bead delivered chemotherapy, tumour ablation, stereotactic radiotherapy, and selective internal radiotherapy contribute to improve survival and may convert initially unresectable patients to operability. Currently evolving areas include biomarker characterisation of tumours, the development of novel systemic agents targeting specific oncogenic pathways, and the potential re-emergence of radical surgical options such as liver transplantation.

Complete Metabolic Response Assessed by FDG PET/CT to FOLFOXIRI-Bevacizumab in First-Line Treatment of BRAFV600E Mutated Metastatic Colorectal Cancer

Triplet chemotherapy (FOLFOXIRI) + bevacizumab regimen is indicated as first-line treatment of BRAF-mutated metastatic colorectal cancer (mCRC). Nevertheless, its proven therapeutic efficacy in clinical trials was solely based on partial morphologic responses assessed by CT. To date, only 1 case of complete response assessed by FDG PET/CT was reported in literature in BRAF-mutated mCRC, but treated with doublet chemotherapy (FOLFIRI) + cetuximab regimen. We report a complete metabolic response assessed by FDG PET/CT, maintained over time (13 months) in a 60-year-old woman with BRAF-mutated mCRC treated by FOLFOXIRI-bevacizumab. This also confirms that FDG PET/CT is emerging as a useful approach for therapeutic assessment of targeted drugs in mCRC.

Synthetic lethality on drug discovery: an update on cancer therapy

INTRODUCTION

A novel anticancer therapy is the need of the hour due to growing incidences of resistance to first line cancer chemotherapy. Synthetic lethality (SL) is one of the new age treatment methods being explored for combating the resistance to anticancer agents. In this method, cell mutations are exploited for the development of new therapeutic agents, where, if there is loss of function of one gene, the cell mutations can still be fixed by alternative machinery but if two genes involved in DNA repair undergo loss of function, it causes lethality to the cell.

AREAS COVERED

The authors condense findings of SL-based novel anticancer regimen. The review emphasizes some of the SL based clinical and preclinical studies of novel targets and therapy.

EXPERT OPINION

SL conceptualizes a resolution against treatment resistance to anticancer regimen by recognition of therapeutic vulnerabilities in particular cancer cells. A multitude of clinical trials associated with SL and DNA repair are being conducted that will be useful in obtaining a clearer picture pertaining to the use of cancer biomarkers and effectiveness of drugs acting via target-based molecular changes. Furthermore, new anticancer regimen focused on personalized medicines will emerge basing their development upon SL.