Combination of Anti-EGFR and Anti-VEGF Drugs for the Treatment of Previously Treated Metastatic Colorectal Cancer: A Case Report and Literature Review

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.

Using a combination of fruquintinib, raltitrexed, and S-1 as a third-line treatment for metastatic colorectal cancer with co-existence of Hodgkin lymphoma: a case report

Background

Patients with metastatic colorectal cancer (mCRC) beyond second line treatment have a poor prognosis. Fruquintinib, regorafenib, trifluridine/tipiracil (TAS-102), panitumumab and cetuximab combined with single-agent chemotherapy regimens are currently recommended as third-line therapies for patients exhibiting disease progression. Effective late-line therapies for mCRC are urgently needed. The FRESCO randomized clinical trial (RCT) prompts fruquintinib as a third-line treatment in advanced colorectal cancer (CRC). A phase II study in our center reported the efficacy and safety of S-1 plus raltitrexed for the treatment of chemo-refractory mCRC. The combination of the fruquintinib, raltitrexed, and S-1 has not been reported in mCRC.

Case Description

This case report presents a patient with mCRC who received third-line treatment with fruquintinib, raltitrexed, and S-1. A 54-year-old male presenting with hematochezia was admitted to West China Hospital of Sichuan University in June 2017 and underwent surgery for a tumor between the rectum and sigmoid colon. Postoperative pathology identified adenocarcinoma (wild-type RAS/RAF, no PIK3CA mutation), and the patient was diagnosed with mCRC (pathological stage, pT3pN1apM0). The mFOLFOX6 regimen was administered. The patient was subsequently diagnosed with Hodgkin lymphoma in May 2018 and treated with the ABVD regimen after multidisciplinary discussions. Liver metastases (intestinal-type adenocarcinoma) were detected in November 2018, and second-line therapy with the FOLFIRI regimen was initiated in January 2019. Lung metastases were identified in September 2019, so the patient was treated with a combination of raltitrexed, S-1, and fruquintinib. A partial response (PR) was detected in November 2019, and the patient underwent resection of the hepatic lesion on November 5, 2020. Computed tomography (CT) images in November 2021 revealed a stable disease; thus, raltitrexed was discontinued, and S-1 and fruquintinib were maintained. The treatment is still responding until the last follow-up (December 2022).

Conclusions

The case was characterized by the simultaneous existence of mCRC and Hodgkin lymphoma, which required management by a multidisciplinary team. Third-line therapy with fruquintinib, raltitrexed, and S-1 achieved a PR that permitted surgical resection and enabled a relatively long progression-free survival. The findings suggest that the three agents regimen might be clinically effective as late-line therapy for mCRC.

Preclinical Evaluation of a Novel Small Molecule LCC-21 to Suppress Colorectal Cancer Malignancy by Inhibiting Angiogenic and Metastatic Signatures

Colorectal cancer (CRC) is one of the most common cancers, and it frequently metastasizes to the liver and lymph nodes. Despite major advances in treatment modalities, CRC remains a poorly characterized biological malignancy, with high reported cases of deaths globally. Moreover, cancer stem cells (CSCs) and their microenvironment have been widely shown to promote colon cancer development, progression, and metastasis. Therefore, an understanding of the underlying mechanisms that contribute to the maintenance of CSCs and their markers in CRC is crucial in efforts to treat cancer metastasis and develop specific therapeutic targets for augmenting current standard treatments. Herein, we applied computational simulations using bioinformatics to identify potential theranostic markers for CRC. We identified the overexpression of vascular endothelial growth factor-α (VEGFA)/β-catenin/matrix metalloproteinase (MMP)-7/Cluster of Differentiation 44 (CD44) in CRC to be associated with cancer progression, stemness, resistance to therapy, metastasis, and poor clinical outcomes. To further investigate, we explored in silico molecular docking, which revealed potential inhibitory activities of LCC-21 as a potential multitarget small molecule for VEGF-A/CTNNB1/MMP7/CD44 oncogenic signatures, with the highest binding affinities displayed. We validated these finding in vitro and demonstrated that LCC-21 inhibited colony and sphere formation, migration, and invasion, and these results were further confirmed by a Western blot analysis in HCT116 and DLD-1 cells. Thus, the inhibitory effects of LCC-21 on these angiogenic and onco-immunogenic signatures could be of translational relevance as potential CRC biomarkers for early diagnosis.

Targeting thymidine phosphorylase alleviates resistance to dendritic cell immunotherapy in colorectal cancer and promotes antitumor immunity

T-cell exhaustion plays a pivotal role in the resistance of microsatellite-stable colorectal cancer (CRC) to immunotherapy. Identifying and targeting T-cell exhaustion-activating mechanisms is a promising strategy to augment the effects of immunotherapy. Here, we found that thymidine phosphorylase (TYMP) plays a decisive role in inducing systemic T-cell exhaustion and abrogating the efficacy of dendritic cell (DC) therapy in a CRC model. Targeting TYMP with tipiracil hydrochloride (TPI) induces immunological cell death (ICD). The combined effects of TPI and imiquimod-activated DCs turn CT26 tumors into immunologically ‘hot’ tumors by inducing ICD in vivo. High-dimensional cytometry analysis revealed T-cell and IFN-γ dependency on the therapeutic outcome. In addition, chemoimmunotherapy converts intratumoral Treg cells into Th1 effector cells and eliminates tumor-associated macrophages, resulting in higher cytotoxic T lymphocyte infiltration and activation. This effect is also associated with the downregulation of PD-L1 expression in tumors, leading to the prevention of T-cell exhaustion. Thus, cooperative and cognitive interactions between dendritic cells and immunogenic cell death induced by therapy with TPI promote the immune response and tumoricidal activities against microsatellite stable colorectal cancer. Our results support TYMP targeting to improve the effects of DC immunotherapy and outcomes in CRC.

Complete Response With Cetuximab-Based Treatment of Metastatic Colorectal Cancers: Two Case Reports and Literature Review

Metastases typically develop before diagnosis and during the treatment of colorectal cancers, while patients with metastatic colorectal cancers (mCRCs) currently have a poor prognosis. In terms of surgical approaches, adjuvant therapies, and targeted therapies, the treatment of mCRCs has had numerous recent advances. As a targeted agent widely used in mCRCs, cetuximab-based treatment is still under dispute due to its side effects and unstable effect. We present two mCRC cases treated with cetuximab-based therapy, of which two patients achieved complete response and without recurrence for over 22 and 84 months, respectively. To better understand the drug usage, we also reviewed the recent achievements and usage precautions of cetuximab in mCRCs. Present and many previous observations support that cetuximab might be a referred drug in the first-line chemotherapy of mCRCs with wild-type RAS and BRAF and proficient mismatch repair.