Treatment dilemmas of cetuximab combined with chemotherapy for metastatic colorectal cancer

Pretreatment Nutritional Status in Combination with Inflammation Affects Chemotherapy Interruption in Women with Ovarian, Fallopian Tube, and Peritoneal Cancer

BACKGROUND

Discontinuing chemotherapy worsens cancer prognosis. This study aimed to investigate the relationship between nutritional status at the start of chemotherapy and chemotherapy discontinuation in patients with ovarian, fallopian tube, and primary peritoneal cancer.

METHODS

This was a retrospective cohort study. One hundred and forty-six patients to whom weekly paclitaxel and carboplatin were administered as postoperative chemotherapy were included. Six courses in 21-day cycles were defined as complete treatment. As nutritional indicators, body mass index, weight change rate, serum albumin, total lymphocyte count, prognostic nutritional index, and C-reactive protein-to-albumin ratio (CAR) were compared between complete and incomplete treatment groups. Patients were divided into two groups according to CAR. The number of chemotherapy cycles was compared between these two groups. A Cox proportional hazard model was used for covariate adjustment.

RESULTS

Several indicators differed between complete and incomplete treatment groups, and among the indicators, CAR had the highest discriminatory ability. The number of chemotherapy cycles was shorter in the high CAR group than in the low CAR group. A high CAR was associated with chemotherapy interruption even after adjusting for covariates.

CONCLUSION

Based on CAR, nutritional status before chemotherapy is suggested to be associated with the risk of chemotherapy discontinuation.

Identification and validation of a novel signature as a diagnostic and prognostic biomarker in colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is one of the most common malignant neoplasms worldwide. Although marker genes associated with CRC have been identified previously, only a few have fulfilled the therapeutic demand. Therefore, based on differentially expressed genes (DEGs), this study aimed to establish a promising and valuable signature model to diagnose CRC and predict patient's prognosis.

METHODS

The key genes were screened from DEGs to establish a multiscale embedded gene co-expression network, protein-protein interaction network, and survival analysis. A support vector machine (SVM) diagnostic model was constructed by a supervised classification algorithm. Univariate Cox analysis was performed to construct two prognostic signatures for overall survival and disease-free survival by Kaplan-Meier analysis, respectively. Independent clinical prognostic indicators were identified, followed by univariable and multivariable Cox analysis. GSEA was used to evaluate the gene enrichment analysis and CIBERSORT was used to estimate the immune cell infiltration. Finally, key genes were validated by qPCR and IHC.

RESULTS

In this study, four key genes (DKC1, FLNA, CSE1L and NSUN5) were screened. The SVM diagnostic model, consisting of 4-gene signature, showed a good performance for the diagnostic (AUC = 0.9956). Meanwhile, the four-gene signature was also used to construct a risk score prognostic model for disease-free survival (DFS) and overall survival (OS), and the results indicated that the prognostic model performed best in predicting the DFS and OS of CRC patients. The risk score was validated as an independent prognostic factor to exhibit the accurate survival prediction for OS according to the independent prognostic value. Furthermore, immune cell infiltration analysis demonstrated that the high-risk group had a higher proportion of macrophages M0, and T cells CD4 memory resting was significantly higher in the low-risk group than in the high-risk group. In addition, functional analysis indicated that WNT and other four cancer-related signaling pathways were the most significantly enriched pathways in the high-risk group. Finally, qRT-PCR and IHC results demonstrated that the high expression of DKC1, CSE1L and NSUN5, and the low expression of FLNA were risk factors of CRC patients with a poor prognosis.

CONCLUSION

In this study, diagnosis and prognosis models were constructed based on the screened genes of DKC1, FLNA, CSE1L and NSUN5. The four-gene signature exhibited an excellent ability in CRC diagnosis and prognostic prediction. Our study supported and highlighted that the four-gene signature is conducive to better prognostic risk stratification and potential therapeutic targets for CRC patients.

Cetuximab-Ag2S quantum dots for fluorescence imaging and highly effective combination of ALA-based photodynamic/chemo-therapy of colorectal cancer cells

Colorectal cancer (CRC) has a poor prognosis and urgently needs better therapeutic approaches. 5-Aminolevulinic acid (ALA) induced protoporphyrin IX (PpIX) based photodynamic therapy (PDT) is already used in the clinic for several cancers but not yet well investigated for CRC. Currently, systemic administration of ALA offers a limited degree of tumour selectivity, except for intracranial tumours, limiting its wider use in the clinic. The combination of effective ALA-PDT and chemotherapy may provide a promising alternative approach for CRC treatment. Herein, theranostic Ag₂S quantum dots (AS-2MPA) optically trackable in near-infrared (NIR), conjugated with endothelial growth factor receptor (EGFR) targeting Cetuximab (Cet) and loaded with ALA for PDT monotherapy or ALA/5-fluorouracil (5FU) for the combination therapy are proposed for enhanced treatment of EGFR(+) CRC. AS-2MPA-Cet exhibited excellent targeting of the high EGFR expressing cells and showed a strong intracellular signal for NIR optical detection in a comparative study performed on SW480, HCT116, and HT29 cells, which exhibit high, medium and low EGFR expression, respectively. Targeting provided enhanced uptake of the ALA loaded nanoparticles by strong EGFR expressing cells and formation of higher levels of PpIX. Cells also differ in their efficiency to convert ALA to PpIX, and SW480 was the best, followed by HT29, while HCT116 was determined as unsuitable for ALA-PDT. The therapeutic efficacy was evaluated in 2D cell cultures and 3D spheroids of SW480 and HT29 cells using AS-2MPA with either electrostatically loaded, hydrazone or amide linked ALA to achieve different levels of pH or enzyme sensitive release. Most effective phototoxicity was observed in SW480 cells using AS-2MPA-ALA-electrostatic-Cet due to enhanced uptake of the particles, fast ALA release and effective ALA-to-PpIX conversion. Targeted delivery reduced the effective ALA concentration significantly which was further reduced with codelivery of 5FU. Delivery of ALA via covalent linkages was also effective for PDT, but required a longer incubation time for the release of ALA in therapeutic doses. Phototoxicity was correlated with high levels of reactive oxygen species (ROS) and apoptotic/necrotic cell death. Hence, both AS-2MPA-ALA-Cet based PDT and AS-2MPA-ALA-Cet-5FU based chemo/PDT combination therapy coupled with strong NIR tracking of the nanoparticles demonstrate an exceptional therapeutic effect on CRC cells and excellent potential for synergistic multistage tumour targeting therapy.

Personalized Medicine in Oncology in the Developing World: Barriers and Concepts to Improve Status Quo

Personalized medicine (PM) has revolutionized oncology management in high human development indexed countries. By interrogating both disease and host factors through a variety of tools, oncologists have been able to better target an individual's cancer, leading to improved outcomes. But both the tools used to define these variables, such as next generation sequencing, large immunohistochemical and fluorescence in situ hybridization (FISH) panels, and the weapons employed against each target are extremely expensive. The expenses have to be measured as not only the direct cost to the patient but also the cost to the system to develop and deploy the necessary infrastructure to optimally use them. However, the concepts of predictive, timely prevention and PM have demonstrated improvement in patient's satisfaction and cost effectiveness. In this paper we will summarize the relevant barriers and challenges that limit the implementation of PM in the developing world with an emphasis on the challenges in Nigeria and Nepal.

Survival benefit of neoadjuvant chemotherapy and surgery versus surgery first for resectable colorectal liver metastases: a cohort study

BACKGROUND

There is continued debate about the survival benefit of neoadjuvant chemotherapy (neoCT) in patients with resectable colorectal liver metastases (CRLM).

METHODS

In this retrospective cohort study, we included 201 patients with metastatic colorectal cancer who underwent their first CRLM resection and achieved resection of all sites of disease. We compared the overall survival (OS) and progression-free survival (PFS) between patients who received neoCT prior to CRLM resection with those who underwent CRLM upfront. A multivariable Cox proportional hazard regression analysis was performed to adjust for potential confounders.

RESULTS

A total of 101 of 201 (51.2%) patients received chemotherapy prior to CRLM resection and 100 of 201 had surgery upfront. Multivariable Cox proportional hazard regression showed no statistically significant difference in the hazard of death for those given neoCT prior to resection of CRLM compared with surgery first for both OS and PFS (OS: hazard ratio 1.74, 95% confidence interval 0.85-3.55, P = 0.127, PFS: hazard ratio 1.42, 95% confidence interval 0.93-2.19, P = 0.107).

CONCLUSION

In our series of patients with metastatic colorectal cancer who achieved surgical resection of all sites of disease, neoCT prior to CRLM resection was not associated with any survival benefit.

Association between imaging response and survival following neoadjuvant chemotherapy in patients with resectable colorectal liver metastases: A cohort study

BACKGROUND

The association between the imaging response (structural or metabolic) to neoadjuvant chemotherapy (neoCT) before colorectal liver metastasis (CRLM) and survival is unclear.

METHOD

A total of 201 patients underwent their first CRLM resection. A total of 94 (47%) patients were treated with neoCT. A multivariable, Cox proportional hazard regression analysis was performed to compare overall survival (OS) and progression-free survival (PFS) between response groups.

RESULTS

Multivariable regression analysis of the CT/MRI (n = 94) group showed no difference in survival (OS and PFS) in patients who had stable disease/partial response (SD/PR) or complete response (CR) versus patients who had progressive disease (PD) (OS: HR, 0.36 (95% CI: 0.11-1.19) p = .094, HR, 0.78 (95% CI: 0.13-4.50) p = .780, respectively), (PFS: HR, 0.70 (95% CI: 0.36-1.35) p = .284, HR, 0.51 (0.18-1.45) p = .203, respectively). In the FDG-PET group (n = 60) there was no difference in the hazard of death for patients with SD/PR or CR versus patients with PD for OS or PFS except for the PFS in the small CR subgroup (OS: HR, 0.75 (95% CI: 0.11-4.88) p = .759, HR, 1.21 (95% CI: 0.15-9.43) p = .857), (PFS: HR, 0.34% (95% CI: 0.09-1.22), p = .097, HR, 0.17 (95% CI: 0.04-0.62) p = .008, respectively).

CONCLUSION

There was no convincing evidence of association between imaging response to neoCT and survival following CRLM resection.

Isolation of Common Light Chain Antibodies from Immunized Chickens Using Yeast Biopanning and Fluorescence-Activated Cell Sorting

The phylogenetic distance between chickens and humans accounts for a strong immune response and a broader epitope coverage compared to rodent immunization approaches. Here the authors report the isolation of common light chain (cLC)-based chicken monoclonal antibodies from an anti-epidermal growth factor receptor (EGFR) immune library utilizing yeast surface display in combination with yeast biopanning and fluorescence-activated cell sorting (FACS). For the selection of high-affinity antibodies, a yeast cell library presenting cLC-comprising fragment antigen binding (Fab) fragments is panned against hEGFR-overexpressing A431 cells. The resulting cell-cell-complexes are sorted by FACS resulting in gradual enrichment of EGFR-binding Fabs in three sorting rounds. The isolated antibodies share the same light chain and show high specificity for EGFR, resulting in selective binding to A431 cells with notable EC50 values. All identified antibodies show very good aggregation propensity profiles and thermostabilities. Additionally, epitope binning demonstrates that these cLC antibodies cover a broad epitope space. Isolation of antibodies from immunized chickens by yeast cell biopanning makes an addition to the repertoire of methods for antibody library screening, paving the way for the generation of cLC-based bispecific antibodies against native mammalian receptors.

Anti-tumor Drug Targets Analysis: Current Insight and Future Prospect

The incidence and mortality of malignant tumors are on the rise, which has become the second leading cause of death in the world. At present, anti-tumor drugs are one of the most common methods for treating cancer. In recent years, with the in-depth study of tumor biology and related disciplines, it has been gradually discovered that the essence of cell carcinogenesis is the infinite proliferation of cells caused by the disorder of cell signal transduction pathways, followed by a major shift in the concept of anti-tumor drugs research and development. The focus of research and development is shifting from traditional cytotoxic drugs to a new generation of anti-tumor drugs targeted at abnormal signaling system targets in tumor cells. In this review, we summarize the targets of anti-tumor drugs and analyse the molecular mechanisms of their effects, which lay a foundation for subsequent treatment, research and development.

Identification and validation of an immune prognostic signature in colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is one of the most common malignant neoplasms worldwide. Although the significant efficacy of immunotherapy has been shown, only limited CRC patients benefit from it. Therefore, we aimed to establish a prognostic signature based on immune-related genes (IRGs) to predict overall survival (OS) and the potential response to immunotherapy in CRC patients.

METHODS

Gene expression profiles and clinical information of CRC patients were collected from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. The prognostic signature composed of IRGs was established using univariate Cox regression and the least absolute shrinkage and selection operator (LASSO) regression analysis. CIBERSORT was used to estimate the immune cell infiltration.

RESULTS

A total of 24 survival-related IRGs were identified from 247 differentially expressed IRGs. Then, 16 IRGs were selected to establish the prognostic signature that stratified the patients into the high-risk and low-risk groups with statistically different survival outcomes. The AUCs of the time-dependent ROC curves indicated that the signature had a strong predictive accuracy in internal and external validation sets. Multivariate cox regression analysis suggested that the signature could also act as an independent prognostic factor for OS. The low-risk group had a higher proportion of immune cell infiltration than the high-risk group, such as CD4 memory resting T cells, activated dendritic cells, and resting dendritic cells. In addition, patients in the high-risk group exhibited higher tumor mutation burden and BRAF mutation.

CONCLUSION

We developed an immune-related prognostic signature to predict the OS and immune status in CRC patients. We believed that our signature is conducive to better stratification and more precise immunotherapy for CRC patients.

Methodological Development of Combination Drug and Radiotherapy in Basic and Clinical Research

Newer technical improvements in radiation oncology have been rapidly implemented in recent decades, allowing an improved therapeutic ratio. The development of strategies using local and systemic treatments concurrently, mainly targeted therapies, has however plateaued. Targeted molecular compounds and immunotherapy are increasingly being incorporated as the new standard of care for a wide array of cancers. A better understanding of possible prior methodology issues is therefore required and should be integrated into upcoming early clinical trials including individualized radiotherapy-drug combinations. The outcome of clinical trials is influenced by the validity of the preclinical proofs of concept, the impact on normal tissue, the robustness of biomarkers and the quality of the delivery of radiation. Herein, key methodological aspects are discussed with the aim of optimizing the design and implementation of future precision drug-radiotherapy trials.

A comprehensively revised strategy that improves the specific activity and long-term stability of clinically relevant 89Zr-immuno-PET agents

Zirconium-89 is currently being used in numerous clinical trials involving monoclonal antibodies and positron emission tomography. This report describes a revised strategy that reduces preparation time while increasing the specific activity of clinically relevant immuno-PET agents. Additionally, it demonstrates that n-acetyl-l-cysteine acts as a superior radioprotective agent that improves long-term stability without compromising antigen affinity in vivo.

Evaluation of the effect of 2-(2,4-dihydroxyphenyl)-4H-benzofuro[3,2-d][1,3]thiazin-4-one on colon cells and its anticancer potential

In this paper, we present the biological effect of the newly synthesized 2-(2,4-dihydroxyphenyl)-4H-benzofuro[3,2-d][1,3]thiazin-4-one (DPBT) on human colon adenocarcinoma cell lines (HT-29 and LS180). Additionally, DPBT cytotoxicity was examined in human colon epithelial cells (CCD 841 CoTr) and human skin fibroblasts (HSF). The studies revealed a significant decrease in the proliferation of cancer cells after exposure to DPBT at concentrations in the range of 10–100 µM. Additionally, DPBT was not toxic to normal CCD 841 CoTr and HSF cells at concentrations that induced inhibition of cancer cell proliferation. The nature of the anti-proliferative action of DPBT in the cell cycle progression in colon cancer cells and the expression of proteins involved in this process were examined by flow cytometry and western blotting, respectively. The investigations demonstrated higher sensitivity of LS180 than HT-29 to the DPBT treatment. The anti-proliferative action of DPBT in LS180 was attributed to cell cycle arrest in the G₁ phase via up-regulation of p27^KIP1 and down-regulation of cyclin D1 and CDK4 proteins.

Uridine 5'-diphospho-glucronosyltrasferase: Its role in pharmacogenomics and human disease

Biotransformation is an enzyme-catalyzed process in which the body converts endogenous compounds, xenobiotics and toxic substances into harmless or easily excreted metabolites. The biotransformation reactions are classified as phase I and II reactions. Uridine 5'-diphospho (UDP)-glucuronosyltransferases (UGTs) are a superfamily of phase II enzymes which have roles in the conjugation of xenobiotics or endogenous compounds, including drugs and bilirubin, with glucuronic acid to make them easier to excrete. The method the human body uses to achieve glucuronidation may be affected by a large interindividual variation due to changes in the sequences of the genes encoding these enzymes. In the last five years, the study of the genetic variants of the UGTs at a molecular level has become important due to its association with several diseases and the ability to predict adverse events due to drug metabolism. In the present review, the structure and the prominent genetic variants of the UGT1A subfamily and their metabolic and clinical implications are described.

Microheterogeneity of therapeutic monoclonal antibodies is governed by changes in the surface charge of the protein

It has previously been shown for individual antibodies, that the microheterogenity pattern can have a significant impact on various key characteristics of the product. The aim of this study to get a more generalized understanding of the importance of microheterogeneity. For that purpose, the charge variant pattern of various different commercially available therapeutic mAb products was compared using Cation-Exchange Chromatography with linear pH gradient antigen affinity, Fc-receptor affinity, antibody dependent cellular cytotoxicity (ADCC) and conformational stability. For three of the investigated antibodies, the basic charge variants showed a stronger binding affinity towards FcγRIIIa as well as an increased ADCC response. Differences in the conformational stability of antibody charge variants and the corresponding reference samples could not be detected by differential scanning calorimetry. The different biological properties of the mAb variants are therefore governed by changes in the surface charge of the protein and not by an altered structure. This can help to identify aspects of microheterogeneity that are critical for product quality and can lead to further improvements in the development and production of therapeutic antibody products.