Capecitabine versus 5-fluorouracil in colorectal cancer: where are we now?

Proton pump inhibitors reduce survival outcomes in patients treated with capecitabine: meta-analysis

Proton pump inhibitors (PPIs) are widely used over-the-counter drugs. The interaction between capecitabine and PPIs is still ambiguous within the literature, with some discrepancies still being present regarding the risks, or benefits, of their concomitant use. This meta-analysis aims to analyse data from the literature regarding both the risk of PPIs on survival in patients treated with capecitabine, as well as their benefits regarding the incidence of hand-foot syndrome (HFS). A total of 17 studies were included after searching PubMed, Medline and Cochrane until October 2022 for the effect of PPIs on the treatment efficacy and pharmacokinetics, and incidence of HFS. Revman Ver. 5.3 was used for all statistical analyses. Our data showed a significant HFS reduction at a relative risk of 0.77 (95% CI: 0.70-085; p < 0.00001) in the PPI-using groups compared to control. Meta-analysis of studies assessing survival, however, showed a reduction in almost all survival aspects, most notably within the recurrence-free survival, with a hazard ratio of 1.75; 95% CI: 1.21-2.53; p = 0.003. Individual data incriminating the use of PPIs with capecitabine is quite limited; however, our robust survival data on around 30,000 patients gave significantly worse survival outcomes, particularly in the (neo)adjuvant setting.

Emerging therapeutic strategies for Wnt-dependent colon cancer targeting macropinocytosis

Aberrations in the Wnt signaling pathway, particularly mutations in genes like APC and β-catenin, are pivotal in initiating and driving the progression of colorectal cancer (CRC), establishing this pathway as a crucial target for therapeutic intervention. Membrane trafficking plays a key role in regulating Wnt signaling by controlling the activation, modulation, and secretion of essential signaling molecules that contribute to CRC progression. This review explores the connection between membrane trafficking and Wnt signaling, with a specific focus on macropinocytosis-an endocytic process involved in nutrient uptake that also plays a role in Wnt signal regulation. The relationship between Wnt signaling and macropinocytosis, critical in both embryonic development and cancer onset, reveals a new dimension for therapeutic intervention. Targeting Wnt signaling through the modulation of macropinocytosis and broader membrane trafficking pathways presents a promising therapeutic strategy, with several candidates already in early clinical trials. These emerging approaches underscore the potential of targeting Wnt and its associated membrane trafficking processes for CRC treatment, aligning with the development of innovative therapies.

Health Disparities among Patients with Cancer Who Received Molecular Testing for Biomarker-Directed Therapy

Health disparities present a barrier to successful oncology treatment. The potential for precision oncology to reduce health disparities has not previously been analyzed. We performed a retrospective analysis of 12,627 patients from six major cancer centers whose tumors underwent molecular testing at Caris Life Sciences between 2010 and 2020. Kaplan-Meier and Cox regression were used to describe and analyze overall survival. The molecular and demographic features of the cohort were analyzed by χ2 and ANOVA tests. Black patients composed 25% of the cohort and White patients 63%. Among this molecularly-tested cohort, there were minimal outcome differences based on race, geographic location, or poverty level. When analyzing the interaction of age, race, and sex, racial-based disparities were noted primarily for young non-White women in the study cohort but were more pronounced for men and women of all ages in the broader patient population within the Surveillance, Epidemiology, and End Results database. Mutations in five genes-APC, EGFR, STK11, TP53, and KRAS-were found to affect overall survival among our cohort, and their prevalence varied by race in specific tumor types. Real-world outcomes data in mutation-defined cohorts also provided additional context to previously reported therapeutic response trends. Our study shows that patients who undergo molecular testing display reduced racial health disparities compared with the general population, whereas persistent racial disparities are influenced by age and sex. Genomic-driven racial disparities should be examined at a tumor lineage-specific level. Increased access to molecular testing for all eligible patients may play a role in improving health equity. Significance: This study is the largest of its kind to analyze health disparities and genomic features among a diverse multiinstitutional cohort of patients who underwent molecular testing. Continuing to increase awareness of and access to molecular testing approaches may help to reduce cancer health disparities and improve outcomes for all patients.

Design, synthesis, molecular modeling and evaluation of 2,4-diaminopyrimidine analogues as promising colorectal cancer drugs

The potential of cyclin-dependent kinases (CDKs) as therapeutic targets in cancer treatment is well established. In this study, we present our investigation into a group of 2,4-diaminopyrimidine derivatives that potently inhibit CDK9 and are cytotoxic when tested in colorectal cancer cell lines. We designed and synthesized forty analogues by altering substitutions at C-2 and C-4 position of the pyrimidine system. Among them, compounds 16 h and 16j exhibited strong inhibitory potency against both CDK9 enzymes (IC50 = 11.4 ± 1.4 nM, IC50 = 10.2 ± 1.3 nM respectively) with a significant preference for one over the other, and cytotoxic potency (IC50 = 61 ± 2 nM, IC50 = 20 ± 1 nM respectively) against HCT-116 was discovered through substantial modifications to its structure. Further investigations revealed that compounds 16 h and 16j were directly bound to CDK9, resulting in the suppression of its downstream signaling pathway. This inhibition of cell proliferation occurred by impeding the progression of the cell cycle and inducing apoptosis in cells by suppressing the phosphoryl RNA pol II Ser2. Significantly, compound 16 h and 16j effectively suppressed tumor growth in a xenograft mouse model and exhibited no apparent toxicity. This indicates that CDK9 inhibitors hold great potential as a therapeutic approach for colorectal cancer treatment. Therefore, the aforementioned discoveries are vital for the development of CDK9 inhibitors for the treatment of cancer.

Parecoxib and 5-Fluorouracil Synergistically Inhibit EMT and Subsequent Metastasis in Colorectal Cancer by Targeting PI3K/Akt/NF-κB Signaling

Colorectal cancer is one of the most common causes of cancer mortality worldwide, and innovative drugs for the treatment of colorectal cancer are continually being developed. 5-Fluorouracil (5-FU) is a common clinical chemotherapeutic drug. Acquired resistance to 5-FU is a clinical challenge in colorectal cancer treatment. Parecoxib is a selective COX-2-specific inhibitor that was demonstrated to inhibit metastasis in colorectal cancers in our previous study. This study aimed to investigate the synergistic antimetastatic activities of parecoxib to 5-FU in human colorectal cancer cells and determine the underlying mechanisms. Parecoxib and 5-FU synergistically suppressed metastasis in colorectal cancer cells. Treatment with the parecoxib/5-FU combination induced an increase in E-cadherin and decrease in β-catenin expression. The parecoxib/5-FU combination inhibited MMP-9 activity, and the NF-κB pathway was suppressed as well. Mechanistic analysis denoted that the parecoxib/5-FU combination hindered the essential molecules of the PI3K/Akt route to obstruct metastatic colorectal cancer. Furthermore, the parecoxib/5-FU combination could inhibit reactive oxygen species. Our work showed the antimetastatic capacity of the parecoxib/5-FU combination for treating colorectal cancers via the targeting of the PI3K/Akt/NF-κB pathway.

Fluorinated Organic Polymers for Cancer Drug Delivery

In the realm of cancer therapy, the spotlight is on nanoscale pharmaceutical delivery systems, especially polymer-based nanoparticles, for their enhanced drug dissolution, extended presence in the bloodstream, and precision targeting achieved via surface engineering. Leveraging the amplified permeation and retention phenomenon, these systems concentrate therapeutic agents within tumor tissues. Nonetheless, the hurdles of systemic toxicity, biological barriers, and compatibility with living systems persist. Fluorinated polymers, distinguished by their chemical idiosyncrasies, are poised for extensive biomedical applications, notably in stabilizing drug metabolism, augmenting lipophilicity, and optimizing bioavailability. Material science heralds the advent of fluorinated polymers that, by integrating fluorine atoms, unveil a suite of drug delivery merits: the hydrophobic traits of fluorinated alkyl chains ward off lipid or protein disruption, the carbon-fluorine bond's stability extends the drug's lifecycle in the system, and a lower alkalinity coupled with a diminished ionic charge bolsters the drug's ability to traverse cellular membranes. This comprehensive review delves into the utilization of fluorinated polymers for oncological pharmacotherapy, elucidating their molecular architecture, synthetic pathways, and functional attributes, alongside an exploration of their empirical strengths and the quandaries they encounter in both experimental and clinical settings.

Hand-foot syndrome in cancer patients on capecitabine: examining prevalence, impacts, and associated risk factors at a cancer centre in Malaysia

INTRODUCTION

Hand-foot syndrome (HFS) significantly impacts quality of life in cancer patients undergoing capecitabine treatment. This study assessed capecitabine-associated HFS prevalence, its impacts on chemotherapy treatment, and identified risk factors in multiracial Malaysian patients.

METHODS

We included adult cancer patients receiving capecitabine at Sarawak General Hospital for at least two cycles from April 1, 2021 to June 30, 2022. HFS rates, time to HFS, and proportions of HFS-related treatment modifications were determined. Characteristics between patients with and without HFS were compared and multivariable logistic regression was used to identify risk factors for all-grade HFS and grade ≥2.

RESULTS

Among 369 patients, 185 (50.1%) developed HFS, with 14.6% experiencing grade ≥2 and 21.6% (40/185) underwent treatment modifications. Risk factors for all-grade HFS include older age (OR 1.03 95%CI 1.01, 1.06), prior chemotherapy (OR 2.09 95%CI 1.22, 3.58), higher capecitabine dose (OR 2.96 95%CI 1.62, 5.38), prolonged treatment (OR 1.36 95%CI 1.21, 1.51), folic acid intake (OR 3.27 95%CI 1.45, 7.35) and lower neutrophil count (OR 0.77 95%CI 0.66, 0.89). For HFS grade ≥2, older age (OR 1.04 95%CI 1.01, 1.08), female sex (OR 2.10 95%CI 1.05, 4.18), Chinese race (OR 2.10 95%CI 1.06, 4.18), and higher capecitabine dose (OR 2.62 95%CI 1.28, 5.35) are significant risk factors. Use of calcium channel blockers were associated with reduced risks of all-grade HFS (OR 0.27, 95%CI 0.12, 0.60) and grade ≥2 (OR 0.21 95%CI 0.06, 0.78).

CONCLUSION

This study provides real-world data on capecitabine-induced HFS in Malaysian patients and identifies risk factors that may offer insights into its understanding and management.

Bacterial amidohydrolases and modified 5-fluorocytidine compounds: Novel enzyme-prodrug pairs

Gene-directed enzyme prodrug therapy is an emerging strategy for cancer treatment based on the delivery of a gene that encodes an enzyme that is able to convert a prodrug into a potent cytotoxin exclusively in target cancer cells. However, it is limited by the lack of suitable enzyme variants and a scarce choice of chemical bonds that could be activated. Therefore, this study is aimed to determine the capability of bacterial amidohydrolases YqfB and D8_RL to activate novel prodrugs and the effect such system has on the viability of eukaryotic cancer cells. We have established cancer cell lines that stably express the bacterial amidohydrolase genes and selected several N4-acylated cytidine derivatives as potential prodrugs. A significant decrease in the viability of HCT116 human colon cancer cell lines expressing either the YqfB or the D8_RL was observed after exposure to the novel prodrugs. The data we acquired suggests that bacterial YqfB and D8_RL amidohydrolases, together with the modified cytidine-based prodrugs, may serve as a promising enzyme-prodrug system for gene-directed enzyme prodrug therapy.

Tuning of the Aggregation Behavior of Fluorinated Polymeric Nanoparticles for Improved Therapeutic Efficacy

Incorporation of fluorinated moieties in polymeric nanoparticles has been shown in many instances to increase their uptake by living cells and, hence, has proven to be a useful approach to enhancing delivery to cells. However, it remains unclear how incorporation of fluorine affects critical transport processes, such as interactions with membranes, intracellular transport, and tumor penetration. In this study, we investigate the influence of fluorine on transport properties using a series of rationally designed poly(oligo(ethylene glycol) methyl ether acrylate)-block-perfluoropolyether (poly(OEGA)_m-PFPE) copolymers. Copolymers with different fluorine contents were prepared and exhibit aggregate in solution in a manner dependent on the fluorine content. Doxorubicin-conjugated poly(OEGA)₂₀-PFPE nanoparticles with lower fluorine content exist in solution as unimers, leading to greater exposure of hydrophobic PFPE segments to the cell surface. This, in turn, results in greater cellular uptake, deeper tumor penetration, as well as enhanced therapeutic efficacy compared to that with the micelle-state nanoaggregates (poly(OEGA)₁₀-PFPE and poly(OEGA)₅-PFPE) with higher fluorine content but with less PFPE exposed to the cell membranes. Our results demonstrate that the aggregation behavior of these fluorinated polymers plays a critical role in internalization and transport in living cells and 3D spheroids, providing important design criteria for the preparation of highly effective delivery agents.