Update on capecitabine in colorectal cancer

Effectiveness of oral fluoropyrimidine monotherapy as adjuvant chemotherapy for high-risk stage II colon cancer

Purpose

Methods

Results

Conclusion

Rosmarinic acid represses colitis-associated colon cancer: A pivotal involvement of the TLR4-mediated NF-κB-STAT3 axis

Previously, we found that rosmarinic acid (RA) exerted anti-inflammatory activities in a dextran sulfate sodium (DSS)-induced colitis model. Here, we investigated the anti-tumor effects of RA on colitis-associated colon cancer (CAC) and the underlying molecular mechanisms. We established an azoxymethane (AOM)/DSS-induced CAC murine model for in vivo studies and used a conditioned media (CM) culture system in vitro. H&E staining, immunohistochemistry, western blot assay, enzyme-linked immunosorbent assay, molecular docking, co-immunoprecipitation, and immunofluorescence assay were utilized to investigate how RA prevented colorectal cancer. In the AOM/DSS-induced CAC murine model, RA significantly reduced colitis severity, inflammation-related protein expression, tumor incidence, and colorectal adenoma development. It significantly modulated toll-like receptor-4 (TLR4)-mediated nuclear factor-kappa B (NF-κB) and signal transducer and activator of transcription 3 (STAT3) activation, thus attenuating the expression of anti-apoptotic factors, which mediate transcription factor-dependent tumor growth. In vitro, RA inhibited CM-induced TLR4 overexpression and competitively inhibited TLR4-myeloid differentiation factor 2 complex in an inflammatory microenvironment. Thus, RA suppressed NF-κB and STAT3 activation in colon cancer cells in an inflammatory microenvironment. Therefore, RA suppressed colitis-associated tumorigenesis in the AOM/DSS-induced CAC murine model and abrogated human colon cancer progression in an inflammatory microenvironment by propitiating TLR4-mediated NF-κB and STAT3 activation, pleiotropically.

Colon Cancer, Version 2.2021, NCCN Clinical Practice Guidelines in Oncology

This selection from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Colon Cancer focuses on systemic therapy options for the treatment of metastatic colorectal cancer (mCRC), because important updates have recently been made to this section. These updates include recommendations for first-line use of checkpoint inhibitors for mCRC, that is deficient mismatch repair/microsatellite instability-high, recommendations related to the use of biosimilars, and expanded recommendations for biomarker testing. The systemic therapy recommendations now include targeted therapy options for patients with mCRC that is HER2-amplified, or BRAF V600E mutation-positive. Treatment and management of nonmetastatic or resectable/ablatable metastatic disease are discussed in the complete version of the NCCN Guidelines for Colon Cancer available at NCCN.org. Additional topics covered in the complete version include risk assessment, staging, pathology, posttreatment surveillance, and survivorship.

Combination of calcineurin B subunit (CnB) and 5-fluorouracil reverses 5-fluorouracil-induced immunosuppressive effect and enhances the antitumor activity in hepatocellular carcinoma

Five-fluorouracil (5-FU) is a widely used chemotherapeutic agent for digestive system tumors; however, continuous use of 5-FU may cause severe side effects, including myelosuppression and immunosuppression. Our previous study revealed that calcineurin B subunit (CnB), an innovative genetic engineering antitumor protein, possesses tumor-suppressive effects with low toxicity. CnB can bind to and activate integrin αM on macrophages, subsequently promoting the expression, and secretion of TNF-related apoptosis-inducing ligand, a specific proapoptotic cytokine. In the present study, whether the combined use of CnB and 5-FU can reverse the myelosuppression, and immunosuppressive effects of 5-FU by reactivating the immune system thus increasing antitumor efficacy, was investigated. It was demonstrated that combined treatment of 5-FU and CnB led to increased tumor-suppressive effects, as indicated by reduced tumor volume and weight when compared with 5-FU or CnB treatment alone in a hepatoma xenograph model. In addition, it was demonstrated that combined treatment inhibited the proliferation of hepatoma cells. Notably, the addition of CnB to 5-FU-based therapy completely reversed the immunosuppressive effect of 5-FU. The spleen index and total number of white blood cells in the combination group were higher compared with that of the 5-FU alone group. Furthermore, pathological examinations indicated that CnB attenuated 5-FU-induced organ damage. Based on these findings, it is proposed that CnB may serve as a novel and promising drug candidate for the improvement of 5-FU-based chemotherapy.

Cytotoxic effects of the newly-developed chemotherapeutic agents 17-AAG in combination with oxaliplatin and capecitabine in colorectal cancer cell lines

The use of heat shock protein 90 inhibitors like 17-allylamino-17-demethoxy-geldanamycin (17-AAG) has been recently introduced as an attractive anticancer therapy. It has been shown that 17-AAG may potentiate the inhibitory effects of some classical anticolorectal cancer (CRC) agents. In this study, two panels of colorectal carcinoma cell lines were used to evaluate the effects of 17-AAG in combination with capecitabine and oxaliplatin as double and triple combination therapies on the proliferation of CRC cell lines. HT-29 and all HCT-116 cell lines were seeded in culture media in the presence of different doses of the mentioned drugs in single, double, and triple combinations. Water-soluble tetrazolium-1 (WST-1) assay was used to investigate cell proliferation 24 h after treatments. Then, dose-response curves were plotted using WST-1outputs, and IC₅₀ values were determined. For double and triple combinations respectively 0.5 × IC₅₀ and 0.25 × IC₅₀ were used. Data was analyzed with the software CompuSyn. Drug interactions were analyzed using Chou-Talalay method to calculate the combination index (CI).The data revealed that 17-AAG shows a potent synergistic interaction (CI < 1) with oxaliplatin and capecitabine in double combinations (0.5 × IC₅₀) in both cell lines. In the case of triple combinations, the findings showed an antagonistic interaction (CI > 1) in HT-29 and a synergistic effect (CI < 1) in HCT-116 (0.25 × IC₅₀) cell lines. It was concluded that double combinations of 17-AAG with oxaliplatin or capecitabine might be effective against HCT-116 and HT-29 cell lines. However, in triple combinations, positive results were seen only against HCT-116. Further investigation is suggested to confirm the effectiveness of these combinations in clinical trials.

Non-covalent interactions involving halogenated derivatives of capecitabine and thymidylate synthase: a computational approach

Capecitabine, a fluoropyrimidine prodrug, has been a frequently chosen ligand for the last one and half decades to inhibit thymidylate synthase (TYMS) for treatment of colorectal cancer. TYMS is a key enzyme for de novo synthesis of deoxythymidine monophosphate and subsequent synthesis of DNA. Recent years have also seen the trait of modifying ligands using halogens and trifluoromethyl (–CF₃) group to ensure enhanced drug performance. In this study, in silico modification of capecitabine with Cl, Br, I atoms and –CF₃ group has been performed. Density functional theory has been employed to optimize the drug molecules and elucidate their thermodynamic and electrical properties such as Gibbs free energy, enthalpy, electronic energy, dipole moment and frontier orbital features (HOMO–LUMO gap, hardness and softness). Flexible and rigid molecular docking have been implemented between drugs and the receptor TYMS. Both inter- and intra-molecular non-covalent interactions involving the amino acid residues of TYMS and the drug molecules are explored in details. The drugs were superimposed on the resolved crystal structure (at 1.9 Å) of ZD1694/dUMP/TYMS system to shed light on similarity of the binding of capecitabine, and its modifiers, to that of ZD1694. Together, these results may provide more insights prior to synthesizing halogen-directed derivatives of capecitabine for anticancer treatment.

XELOX vs. FOLFOX in metastatic colorectal cancer: An updated meta-analysis

This meta-analysis aims to evaluate chemotherapy with XELOX (capecitabine plus oxaliplatin) versus FOLFOX (fluorouracil plus oxaliplatin) as a treatment for metastatic colorectal cancer (mCRC) in terms of efficacy and safety. Only randomized controlled trials (RCTs) comparing XELOX versus FOLFOX were included. A total of 4,363 patients from eight RCTs were available for analysis. Pooled analysis revealed that there were no statistical differences between both arms in OS, and ORR. XELOX arm had a higher incidence of thrombocytopenia, hand-foot syndrome, and diarrhea, whereas neutropenia had a higher incidence in the FOLFOX group. For mCRC, the effect of XELOX is similar to FOLFOX.

Vorinostat synergises with capecitabine through upregulation of thymidine phosphorylase

Background:

Potentiation of anticancer activity of capecitabine is required to improve its therapeutic index. In colorectal cancer (CRC) cells, we evaluated whether the histone deacetylase-inhibitor vorinostat may induce synergistic antitumour effects in combination with capecitabine by modulating the expression of thymidine phosphorylase (TP), a key enzyme in the conversion of capecitabine to 5-florouracil (5-FU), and thymidylate synthase (TS), the target of 5-FU.

Methods:

Expression of TP and TS was measured by real-time PCR, western blotting and immunohistochemistry. Knockdown of TP was performed by specific small interfering RNA. Antitumour activity of vorinostat was assessed in vitro in combination with the capecitabine active metabolite deoxy-5-fluorouridine (5′-DFUR) according to the Chou and Talay method and by evaluating apoptosis as well as in xenografts-bearing nude mice in combination with capecitabine.

Results:

Vorinostat induced both in vitro and in vivo upregulation of TP as well as downregulation of TS in cancer cells, but not in ex vivo treated peripheral blood lymphocytes. Combined treatment with vorinostat and 5′-DFUR resulted in a synergistic antiproliferative effect and increased apoptotic cell death in vitro. This latter effect was impaired in cells where TP was knocked. In vivo, vorinostat plus capecitabine potently inhibited tumour growth, increased apoptosis and prolonged survival compared with control or single-agent treatments.

Conclusions:

Overall, this study suggests that the combination of vorinostat and capecitabine is an innovative antitumour strategy and warrants further clinical evaluation for the treatment of CRC.

Rationally designed pharmacogenomic treatment using concurrent capecitabine and radiotherapy for glioblastoma; gene expression profiles associated with outcome

PURPOSE

Previous preclinical studies suggested that concurrent capecitabine and radiation could be an effective new treatment modality for glioblastoma (GBM). In the current study, we investigate toxicity and response to this regimen and explore associations between gene expression and patient outcome.

EXPERIMENTAL DESIGN

Eighteen newly diagnosed GBM patients received concurrent capecitabine at 625 mg/m2 BID (25% escalation) and irradiation (60 Gy total) for 6 weeks followed by 4 weeks of capecitabine only. Maintenance capecitabine was administered for 14 days every 3 weeks until progression or unacceptable toxicity. Expression analysis of 94 genes involved in capecitabine metabolism and radiation response was done on tissues obtained before therapy. The relationship of gene expression with time-to-progression (TTP) and overall survival (OS) was investigated using univariate Cox proportional hazards regression, semi-supervised principle component analysis, and class prediction modeling.

RESULTS

The maximum tolerated dose of capecitabine was 625 mg/m2 BID. Median patient TTP and OS were 247 and 367 days, respectively. Cox regression identified 24 genes significantly (P<0.025) associated with patient outcome. Semi-supervised principle component analysis identified two patient populations significantly different in both TTP (P=0.005) and OS (P=0.015). Class prediction modeling determined that eight genes (RAD54B, MTOR, DCTD, APEX2, TK1, RRM2, SLC29A1, and ERCC6) could collectively classify patients into outcome subgroups with 100% accuracy and precision.

CONCLUSIONS

Capecitabine and concurrent radiation for newly diagnosed GBM seems to be well tolerated and comparable to temozolomide and radiation. A gene expression profile predictive of patient outcome that may be useful in patient stratification for therapy was also elucidated.

Paralytic Ileus Associated with Capecitabine

Paralytic ileus is a temporary arrest of intestinal peristalsis. We report on two patients with breast cancer who developed paralytic ileus following treatment with capecitabine. The pathophysiology of this disorder and its possible connection to capecitabine are described with the aim of promoting the early recognition of the clinical picture so that unnecessary surgery can be avoided.

Targeted therapy of cancer: new roles for pathologists in colorectal cancer

Personalized/individualized/tailored therapy for each patient is an important goal for improving the outcome of patients with colorectal adenocarcinoma and includes the intention to maximize efficacy and minimize toxicity of chemotherapeutic agents. Numerous barriers must be overcome to reach this goal because outcome is affected by an unholy trinity of tumor characteristics that include somatic alterations at the DNA, RNA, and protein level; patient characteristics that include germline genetic differences such as polymorphisms in enzymes affecting the metabolism of chemotherapeutic agents; and environmental exposures and factors that include diet and physical activity. At present, evaluation of epidermal growth factor receptor (EGFR) expression by immunohistochemistry in colorectal adenocarcinoma is generally required for treatment with one of the monoclonal antibody therapies directed against that target, despite the absence of evidence for predictive value of the assay, whereas EGFR fluorescent in situ hybridization (FISH) may be predictive. In addition, the Food and Drug Administration of the United States now requires a 'black box' warning on the packaging of irinotecan for evaluation of germline polymorphism in UGT1A1, the gene mutated in Gilbert's syndrome, for potential reduction of drug dosage in patients with the UGT1A1*28 polymorphism. Numerous other potential markers have been identified but have not yet reached levels of evidence that support their routine usage. For example, KRAS gene mutation appears to preclude improved survival after therapy with monoclonal antibody therapy directed at EGFR, and extensive DNA methylation is associated with lack of efficacy of 5-fluorouracil (5-FU)-based chemotherapy. Additional markers will come into routine usage as reports of research studies continue to appear in the literature. Clinical trials driven by molecular targets and agents directed against them, and understanding of the conflicting data on utility of markers reported in the literature, are needed to advance the field.

Pharmacogenetic approach for capecitabine or 5-fluorouracil selection to be combined with oxaliplatin as first-line chemotherapy in advanced colorectal cancer

We studied the role of TS (5'VNTR, 5'SNP and 3'UTR), XRCC1-399, XPD-751, ERCC1-118 and XRCC3-241 genetic polymorphisms in tailoring fluroropyrimidine/oxaliplatin treatment. For this purpose, 110 XELOX (capecitabine/oxaliplatin)- or FUOX (fluorouracil/oxaliplatin)-treated metastatic colorectal cancer patients were selected prospectively for genotyping. In the FUOX group, TS-3'UTR +6bp/+6bp (hazards ratio, HR=2.62, p=0.007) and ERCC1-118C/T or C/C (HR=1.96, p=0.050) genotypes correlated with a shorter progression-free survival (PFS). When analysed jointly, the higher the number of favourable genotypes (FG) the longer the PFS (6.8m, 9.6m and 25.8m for 0, 1 or 2 FG; p=0.005). Disease-control rate was 100% in patients with 2 FG (87% and 38.5% for 1 or 0 FG; p=0.001). In the multivariate analysis, ERCC1-118 (HR=2.12, p=0.0037) and TS-3'UTR (HR=2.68, p=0.006) were strong independent prognostic factors. According to this, patients harbouring TS-3'UTR +6bp/+6bp and ERCC1-118C/T or C/C genotypes may better receive capecitabine instead of 5FU in an oxaliplatin-based first-line treatment.

The novel combination of chlorpromazine and pentamidine exerts synergistic antiproliferative effects through dual mitotic action

Combination therapy has proven successful in treating a wide variety of aggressive human cancers. Historically, combination treatments have been discovered through serendipity or lengthy trials using known anticancer agents with similar indications. We have used combination high-throughput screening to discover the unexpected synergistic combination of an antiparasitic agent, pentamidine, and a phenothiazine antipsychotic, chlorpromazine. This combination, CRx-026, inhibits the growth of tumor cell lines in vivo more effectively than either pentamidine or chlorpromazine alone. Here, we report that CRx-026 exerts its antiproliferative effect through synergistic dual mitotic action. Chlorpromazine is a potent and specific inhibitor of the mitotic kinesin KSP/Eg5 and inhibits tumor cell proliferation through mitotic arrest and accumulation of monopolar spindles. Pentamidine treatment results in chromosomal segregation defects and delayed progression through mitosis, consistent with inhibition of the phosphatase of regenerating liver family of phosphatases. We also show that CRx-026 synergizes in vitro and in vivo with the microtubule-binding agents paclitaxel and vinorelbine. These data support a model where dual action of pentamidine and chlorpromazine in mitosis results in synergistic antitumor effects and show the importance of systematic screening for combinations of targeted agents.

Targeting platelet-derived endothelial cell growth factor/thymidine phosphorylase for cancer therapy

Thymidine phosphorylase (TP) is a key enzyme in the pyrimidine nucleoside salvage pathway, but it also recognizes and inactivates various anti-cancer chemotherapeutic agents. Moreover, TP is identical to platelet-derived endothelial cell growth factor (PD-ECGF), an angiogenic factor with anti-apoptotic properties. Increased expression of PD-ECGF/TP is found in many tumor and stromal cells, and elevated TP levels are associated with aggressive disease and/or poor prognosis. Thus, progression and metastasis of TP-expressing tumors might be abrogated by TP inhibitors that are used as single agents or in combination with (TP-sensitive) nucleoside analogues. On the other hand, increased TP activity in tumors may be exploited for the tumor-specific activation of fluoropyrimidine prodrugs, such as capecitabine. This review will focus on the different biological activities of PD-ECGF/TP and their implications for cancer progression and treatment.

Preoperative administration of xeloda on the angiogenesis and expression of thymidine phosphorylase/platelet-derived endothelial cell growth factor in colorectal cancer

AIM: To investigate the effect of capecitabine (xeloda) by preoperation administration on the microvessel density (MVD) and expression of thymidine phosphorylase/platelet-derived endothelial cell growth factor (TP/PD-ECGF) in patients with colorectal cancer.

METHODS: Immunohistochemical staining of CD34 and TP/PD-ECGF monoclonal antibodies was performed in 32 colorectal cancer patients with preoperative xeloda chemotherapy and 25 cases without chemotherapy (served as controls), and then the expression of TP/PD-ECGF and MVD were analyzed.

RESULTS: The positive rate of TP/PD-ECGF expression in patients with chemotherapy was significantly lower than that in the controls (31.2% vs 60.0%, P < 0.05). As compared with that in the controls, the value of MVD in patients with chemotherapy was markedly different (20.7 ± 8.5 vs 42.3 ± 7.8, P < 0.05).

CONCLUSION: Preoperation chemotherapy of xeloda can decrease the activity of TP/PD-ECGF and inhibit the angiogenesis in colorectal cancer.

Therapy for Metastatic Colorectal Cancer

Median overall survival of metastatic colorectal cancer patients treated with first- and second-line combination chemotherapy now extends to more than 20 months in some studies. Chemotherapy alone, particularly when oxaliplatin is included, may allow potentially curative resection of advanced disease. There is evidence that the addition of antibodies targeted against vascular endothelial growth factor or the epidermal growth factor receptor will further improve prospects for patients with advanced and metastatic disease. However, the optimum sequencing of chemo- and biological therapies remains to be established, as does the potential contribution of numerous agents in development.