Cetuximab monotherapy and cetuximab plus irinotecan in irinotecan-refractory metastatic colorectal cancer

Current Targeted Therapy for Metastatic Colorectal Cancer

Colorectal cancer (CRC) is the third most common type of cancer and the second leading cause of cancer deaths worldwide. Surgery or surgery plus radiotherapy and/or chemotherapy for patients with metastatic CRC (mCRC) were accepted as the main therapeutic strategies until the early 2000s, when targeted drugs, like cetuximab and bevacizumab, were developed. The use of targeted drugs in clinical practice has significantly increased patients' overall survival. To date, the emergence of several types of targeted drugs has opened new possibilities and revealed new prospects for mCRC treatment. Therapeutic strategies are continually being updated to select the most suitable targeted drugs based on the results of clinical trials that are currently underway. This review discusses the up-to date molecular evidence of targeted therapy for mCRC and summarizes the Food and Drug Administration-approved targeted drugs including the results of clinical trials. We also explain their mechanisms of action and how these affect the choice of a suitable targeted therapy.

Development of a spermine lipid for transient antibody expression

Transient expression is the only way to quickly obtain a small scale of antibodies for biomedical research and therapeutic evaluation. The agents for transfecting the suspension cells, e.g. PEI or commercial agents, either lack efficiency or excessively expensive. Herein, a novel spermine-based lipid was developed and fabricated into a cationic liposome for antibody expression. This new transfection agent, designated as sperminoliposome, is feasible, cheap, and highly effective to produce antibodies. Compared to PEI, a 3 times higher yield of antibody was obtained by sperminoliposome during the transient expression of cetuximab in suspension 293F cells. Characterizations confirmed that the expressed antibody is fully functional and eligible for further research. Our study provides an effective tool for the rapid production of antibodies economically and feasibly.

Exosomes derived from MDR cells induce cetuximab resistance in CRC via PI3K/AKT signaling‑mediated Sox2 and PD‑L1 expression

The anti-EGFR antibody cetuximab is used as a first-line targeted therapeutic drug in colorectal cancer. It has previously been reported that the efficacy of the EGFR antibody cetuximab is limited by the emergence of acquired drug resistance. In our previous study the transmissibility effect of exosomes from drug resistant tumor cells to sensitive tumor cells was identified. It can therefore be hypothesized that drug resistant cells might affect neighboring and distant cells via regulation of exosome composition and behavior. However, the mechanism of exosomes in KRAS-wild-type colorectal cancer (CRC) remains unknown. In the present study, functional analysis of overall survival post-diagnosis in patients with KRAS wild-type and those with mutant CRC was performed using human CRC specimens. Furthermore, it was demonstrated that multidrug resistance (MDR) cancer cell-derived exosomes were potentially a key factor, which promoted cetuximab-resistance in CRC cells and reduced the inhibitory effect of cetuximab in CRC xenograft models. The Cell Counting Kit-8 and colony formation assays were performed to assess the effects of exosomes derived from CRC/MDR cells on cetuximab resistance. Sphere formation assay results demonstrated that exosomes derived from CRC/MDR cells altered the self-renewal and multipotential ability of stem-cell-associated markers and facilitated resistance to cetuximab in cetuximab-sensitive cells. Furthermore, exosomes derived from CRC/MDR cells decreased sensitivity to cetuximab via the activation of PI3K/AKT signaling, which promoted Sox2 and programmed death-ligand 1 (PD-L1) mRNA and protein expression according to reverse transcription-quantitative PCR, western blotting and immunohistochemistry analyses, as well as apoptosis resistance both in vitro and in vivo according to a TUNEL assay. In conclusion, the results of the present study demonstrated that exosomes derived from CRC/MDR cells may promote cetuximab resistance in KRAS wild-type cells via activation of the PI3K/AKT signaling pathway-mediated expression of Sox2 and PD-L1, which will be useful for investigating a potential clinical target in predicting cetuximab resistance.

Long-Term 5-Year Response to Pembrolizumab, Bevacizumab, and Capecitabine Regimen in a Metastatic Colon Cancer Patient with MSI-High and KRAS Mutation: Case Report

With an estimated 1.88 million new cases and 0.92 million deaths in 2020, colorectal cancer accounts for nearly one-tenth of all new cancer and cancer-related deaths worldwide. Nearly half of the patients of colorectal cancer are diagnosed with metastatic or inoperable disease with a very dismal 5-year survival rate. Chemotherapy, targeted therapy, and immunotherapy have been used to treat metastatic disease, either alone or in combination. We present a case of recurrent metastatic colon carcinoma with KRAS exon 2 mutation and high microsatellite instability that was treated with a combination regimen of bevacizumab, capecitabine oral chemotherapy, and pembrolizumab immunotherapy. At nearly 5 years of treatment, the patient is alive with good performance status and improved quality of life owing to a favorable response to the molecular profiling-based treatment approach.

Cancer: slaying the nine-headed Hydra

Modern medicine continues to evolve, and the treatment armamentarium for various diseases grows more individualized across a breadth of medical disciplines. Cure rates for infectious diseases that were previously pan-fatal approach 100% because of the identification of the specific pathogen(s) involved and the use of appropriate combinations of drugs, where needed, to completely extinguish infection and hence prevent emergence of resistant strains. Similarly, with the assistance of technologies such as next-generation sequencing and immunomic analysis as part of the contemporary oncology armory, therapies can be tailored to each tumor. Importantly, molecular interrogation has revealed that metastatic cancers are distinct from each other and complex. Therefore, it is conceivable that rational personalized drug combinations will be needed to eradicate cancers, and eradication will be necessary to mitigate clonal evolution and resistance.

Targeted Therapy and Personalized Medicine

Targeted therapy and personalized medicine are novel emerging disciplines of cancer research intended for treatment and prevention. One of the most significant advancements in modern oncology is the shift from an organ-centric strategy to a personalized strategy guided by deep molecular analysis. This shift in view, which focuses on the tumour's precise molecular changes, has paved the way for individualized treatment. Researchers and clinicians are using targeted therapies to select the best treatment available based on the molecular characterization of malignant cancer. In the treatment of a cancer, personalized medicine entails the use of genetic, immunological, and proteomic profiling to provide therapeutic alternatives as well as prognostic information about cancer. In this book, targeted therapies and personalized medicine have been covered for specific malignancies, including latest FDA-approved targeted therapies and it also sheds light on effective anti-cancer regimens and drug resistance. This will help to enhance our ability to conduct individualized health planning, make early diagnoses, and choose optimal medications for each cancer patient with predictable side effects and outcomes in a quickly evolving era. Various applications and tools' capacity have been improved for early diagnosis of cancer and the growing number of clinical trials that choose specific molecular targets reflects this predicament. Nevertheless, there are several limitations that must need to be addressed. Hence, in this chapter, we will discuss recent advancements, challenges, and opportunities in personalized medicine for various cancers, with a specific emphasis on target therapies in diagnostics and therapeutics.

Cancer Chemoresistance; Recent Challenges and Future Considerations

Cancer remains one of the serious health hazards and major causes of human mortality across the world. Despite the development of many typical antineoplastic drugs and introduction of novel targeted agents, chemoresistance constitutes a major challenge in the effective therapeutic management of cancer. Drug inactivation, efflux of anticancer agents, modification of target sites, enhanced repair of DNA damage, apoptosis failure and induction of epithelial-mesenchymal transition are the principal mechanisms of cancer chemoresistance. Moreover, epigenetics, cell signaling, tumor heterogeneity, stem cells, microRNAs, endoplasmic reticulum, tumor microenvironment and exosomes have also been implicated in the multifaceted phenomenon of anticancer drug resistance. The tendency of resistance is either intrinsically possessed or subsequently acquired by cancerous cells. From clinical oncology standpoint, therapeutic failure and tumor progression are the most probable consequences of cancer chemoresistance. Combination therapy can help to overcome the issue of drug resistance, and therefore, the development of such treatment regimens is recommended for counteracting the emergence and dissemination of cancer chemoresistance. This chapter outlines the current knowledge on underlying mechanisms, contributory biological factors and likely consequences of cancer chemoresistance. Besides, prognostic biomarkers, diagnostic methods and potential approaches to overcome the emergence of antineoplastic drug resistance have also been described.

Recent and Future Strategies to Overcome Resistance to Targeted Therapies and Immunotherapies in Metastatic Colorectal Cancer

Colorectal cancer (CRC) is the third most common cause of cancer-related deaths worldwide, and 20% of patients with CRC present at diagnosis with metastases. The treatment of metastatic CRC is based on a fluoropyrimidine-based chemotherapy plus additional agents such as oxaliplatin and irinotecan. To date, on the basis of the molecular background, targeted therapies (e.g., monoclonal antibodies against epidermal growth factor receptor or inhibiting angiogenesis) are administered to improve the treatment of metastatic CRC. In addition, more recently, immunological agents emerged as effective in patients with a defective mismatch repair system. The administration of targeted therapies and immunotherapy lead to a significant increase in the survival of patients; however these drugs do not always prove effective. In most cases the lack of effectiveness is due to the development of primary resistance, either a resistance-inducing factor is already present before treatment or resistance is acquired when it occurs after treatment initiation. In this review we describe the most relevant targeted therapies and immunotherapies and expand on the reasons for resistance to the different approved or under development targeted drugs. Then we showed the possible mechanisms and drugs that may lead to overcoming the primary or acquired resistance in metastatic CRC.

Broad reactivity and enhanced potency of recombinant anti-EGFR × anti-CD3 bispecific antibody-armed activated T cells against solid tumours

Introduction: Bispecific antibody (BiAb)-armed activated T cells (BATs) comprise an adoptive T cell therapy platform for treating cancer. Arming activated T cells (ATC) with anti-CD3 x anti-tumour associated antigen (TAA) BiAbs converts ATC into non-major histocompatibility complex (MHC)-restricted anti-tumour cytotoxic T lymphocytes (CTLs). Binding of target antigens via the BiAb bridge enables specific anti-tumour cytotoxicity, Th1 cytokines release, and T cell proliferation. Clinical trials in breast, prostate, and pancreatic cancer using BATs armed with chemically heteroconjugated BiAbs demonstrated safety, feasibility, induction of anti-tumour immune responses and potential increases in overall survival (OS).Objectives: The primary objective of this study was to develop a recombinant BiAb that confers enhanced anti-tumour activity of BATs against a broad range of solid tumours.Methods: A recombinant anti-epidermal growth factor receptor (EGFR) x anti-CD3 (OKT3) BiAb (rEGFRBi) was designed and expressed in CHO cells, used to arm ATC (rEGFR-BATs), and tested for specific cytotoxicity against breast, pancreatic and prostate cancers and glioblastoma.Results: rEGFR-BATs exhibit remarkably enhanced specific cytotoxicity and T1 cytokine secretion against a wide range of solid tumour cell lines vs. their respective chemically-heteroconjugated BATs.Conclusion: rEGFR-BATs may provide a "universal" T cell therapy for treating a wide range of solid tumours. KEY MESSAGEA (Gly4Ser)6 linker between the variable light and heavy chains of an scFv fused to the N-terminus of a heavy chain antibody confers unexpected stability to the heavy chain fusion protein and supports the efficient expression of the bispecific antibody.Arming of activated T cells with the rEGFRBi greatly enhances the relative cytotoxicity and Th1 cytokine secretion of theT cells relative to a chemically heteroconjugated BiAbs.rEGFR-BATs are promising candidates for the treatment of a broad range of solid tumours.

Incidence and associated factors of cetuximab-induced hypersensitivity infusion reactions in 1392 cancer patients treated in four French areas: a possible association with Lyme disease?

BACKGROUND

Previous studies have observed an increased incidence of Cetuximab-induced hypersensitivity infusion reactions (CI-IRs) in the southeastern states of the USA. Tick's bites were suspected of generating cross-reactions between cetuximab and alpha-gal. This study aims was to describe the incidence and associated risk factors of CI-IRs, in the French areas chosen according to their Lyme disease incidence.

PATIENTS AND METHODS

A retrospective chart review was conducted on patients that received cetuximab infusion from January 2010 to June 2019 in 4 French areas with different Lyme disease incidence rates.

RESULTS

Of 1392 patients, 117 (8.4%) experienced a CI-IR, including 68 severe (grade 3 or 4) reactions (4.9%). This CI-IR incidence was significantly higher in the Lyme disease high-risk area than in the other areas (13.2% versus 7.1%, 8.1% and 6.4%; P = 0.016). Sex (P = 0.53), premedication (P = 0.91), primary cancer location (P = 0.46) and chemotherapy regimen type (P = 0.78) had no impact on CI-IR incidence in the overall population. In the head and neck squamous cell carcinoma (HNSCC) patient subgroup, CI-IRs were significantly more frequent in the high-risk area (16.4% versus 6.7%, 7.1% and 7.0%; P = 0.0015).

CONCLUSION

This study suggests that patients treated in the French area with the highest incidence of Lyme disease are at a higher risk of CI-IRs.

Current concepts of anti-EGFR targeting in metastatic colorectal cancer

Anti-EGFR targeting is one of the key strategies in the treatment of metastatic colorectal cancer (mCRC). For almost two decades oncologists have struggled to implement EGFR antibodies in the mCRC continuum of care. Both sidedness and RAS mutational status rank high among the predictive factors for the clinical efficacy of EGFR inhibitors. A prospective phase III trial has recently confirmed that anti-EGFR targeting confers an overall survival benefit only in left sided RAS-wildtype tumors when given in first line. It is a matter of discussion if more clinical benefit can be reached by considering putative primary resistance mechanisms (e.g., HER2, BRAF, PIK3CA, etc.) at this early stage of treatment. The value of this procedure in daily routine clinical utility has not yet been clearly delineated. Re-exposure to EGFR antibodies becomes increasingly crucial in the disease journey of mCRC. Yet re- induction or re-challenge strategies have been problematic as they relied on mathematical models that described the timely decay of EGFR antibody resistant clones. The advent of liquid biopsy and the implementation of more accurate next-generation sequencing (NGS) based high throughput methods allows for tracing of EGFR resistant clones in real time. These displays the spatiotemporal heterogeneity of metastatic disease compared to the former standard radiographic assessment and re-biopsy. These techniques may move EGFR inhibition in mCRC into the area of precision medicine in order to apply EGFR antibodies with the increase or decrease of EGFR resistant clones. This review critically discusses established concepts of tackling the EGFR pathway in mCRC and provides insight into the growing field of liquid biopsy guided personalized approaches of EGFR inhibition in mCRC.

Recruiting Immunity for the Fight against Colorectal Cancer: Current Status and Challenges

Cancer immunotherapies have changed the landscape of cancer management and improved the standard treatment protocols used in multiple tumors. This has led to significant improvements in progression-free survival and overall survival rates. In this review article, we provide an insight into the major immunotherapeutic methods that are currently under investigation for colorectal cancer (CRC) and their clinical implementations. We emphasize therapies that are based on monoclonal antibodies (mAbs) and adoptive cell therapy, their mechanisms of action, their advantages, and their potential in combination therapy. We also highlight the clinical trials that have demonstrated both the therapeutic efficacy and the toxicities associated with each method. In addition, we summarize emerging targets that are now being evaluated as potential interventions for CRC. Finally, we discuss current challenges and future direction for the cancer immunotherapy field.

Pharmacokinetics and pharmacodynamics of approved monoclonal antibody therapy for colorectal cancer

INTRODUCTION

The introduction of monoclonal antibodies to the chemotherapy backbone treatment has challenged the paradigm of metastatic colorectal cancer (mCRC) treatment. Their mechanism of action and pharmacokinetics are complex but important to understand in order to improve patient selection and treatment outcomes for mCRC population.

AREAS COVERED

This review examines the scientific data, pharmacodynamics, and pharmacokinetics of approved monoclonal antibodies used to treat mCRC patients, including agents targeting signaling via VEGFR (bevacizumab and ramucirumab), EGFR (cetuximab and panitumumab), HER2/3 target therapy, and immunotherapy agents such as pembrolizumab or nivolumab. Efficacy and mechanism of action of bispecific antibodies are also covered.

EXPERT OPINION

mCRC is a heterogeneous disease and the optimal selection and sequence of treatments is challenging. Monoclonal antibodies have complex pharmacokinetics and pharmacodynamics, with important interactions between them. The arrival of bioequivalent molecules to the market increases the need for the characterization of pharmacokinetics and pharmacodynamics of classic monoclonal antibodies to reach bioequivalent novel molecules.

Molecular pathogenesis, targeted therapies, and future perspectives for gastric cancer

Gastric cancer is a major source of global cancer mortality with limited treatment options and poor patient survival. As our molecular understanding of gastric cancer improves, we are now beginning to recognize that these cancers are a heterogeneous group of diseases with incredibly unique pathogeneses and active oncogenic pathways. It is this molecular diversity and oftentimes lack of common oncogenic driver mutations that bestow the poor treatment responses that oncologists often face when treating gastric cancer. In this review, we will examine the treatments for gastric cancer including up-to-date molecularly targeted therapies and immunotherapies. We will then review the molecular subtypes of gastric cancer to highlight the diversity seen in this disease. We will then shift our discussion to basic science and gastric cancer mouse models as tools to study gastric cancer molecular heterogeneity. Furthermore, we will elaborate on a molecular process termed paligenosis and the cyclical hit model as key events during gastric cancer initiation that impart nondividing mature differentiated cells the ability to re-enter the cell cycle and accumulate disparate genomic mutations during years of chronic inflammation and injury. As our basic science understanding of gastric cancer advances, so too must our translational and clinical efforts. We will end with a discussion regarding single-cell molecular analyses and cancer organoid technologies as future translational avenues to advance our understanding of gastric cancer heterogeneity and to design precision-based gastric cancer treatments. Elucidation of interpatient and intratumor heterogeneity is the only way to advance future cancer prevention, diagnoses and treatment.

Distinct Genomic Profiles are Associated With Conversion to Resection and Survival in Patients With Initially Unresectable Colorectal Liver Metastases Treated With Systemic and Hepatic Artery Chemotherapy

OBJECTIVE

To examine genomic correlates of conversion to resection (CTR and overall survival (OS) in patients with initially unresectable colorectal liver metastasis (IU-CRLM) treated with combination systemic and hepatic artery infusion (HAI) chemotherapy.

BACKGROUND

In patients presenting with IU-CRLM, combination systemic and HAI chemotherapy enables CTR with associated long-term OS in a subset of patients. Genomic correlates of CTR and OS in IU-CRLM have not been previously explored.

METHODS

Specimens from IU-CRLM patients receiving systemic/HAI chemotherapy (2003-2017) were submitted for next-generation sequencing. Fisher Exact test assessed associations with CTR, and Kaplan-Meier/Cox methods assessed associations with OS from HAI initiation.

RESULTS

Of 128 IU-CRLM patients, 51 (40%) underwent CTR at median 6 months (range: 3-35) from HAI initiation. CTR and persistently unresectable cohorts differed significantly in preoperative systemic chemotherapy exposure, node-positive primary status, and size of largest liver metastasis. Median and 5-year OS was 66 months and 51%. CTR was associated with prolonged survival (time-dependent HR 0.23,95% CI: 0.12-0.46, P < 0.001). The most frequently altered genes were APC (81%), TP53 (77%), and KRAS (37%). Oncogenic mutations in SOX9 and BRAF were associated with CTR. BRAF mutations, any RAS pathway alterations, and co-altered RAS/RAF-TP53 mutations wereassociated with worse survival. Classification and regression tree analysis defined prognostically relevant clusters of genomic risk to reveal co-altered RAS/RAF-TP53 as the highest risk subgroup. Co-altered RAS/RAF-TP53 remained independently associated with worse survival (HR 2.52, 95% CI: 1.37-4.64, P = 0.003) after controlling for CTR, number of liver metastases, and preoperative extrahepatic disease.

CONCLUSIONS

Distinct genomic profiles are associated with CTR and survival in patients with IU-CRLM treated with HAI/systemic chemotherapy. Presence of SOX9, BRAF , and co-altered RAS/RAF- TP53 mutations are promising biomarkers that, when validated in larger datasets, may impact treatment of IU-CRLM patients.

Anti-tumor efficacy of a potent and selective non-covalent KRASG12D inhibitor

Recent progress in targeting KRAS^G12C has provided both insight and inspiration for targeting alternative KRAS mutants. In this study, we evaluated the mechanism of action and anti-tumor efficacy of MRTX1133, a potent, selective and non-covalent KRAS^G12D inhibitor. MRTX1133 demonstrated a high-affinity interaction with GDP-loaded KRAS^G12D with K_D and IC₅₀ values of ~0.2 pM and <2 nM, respectively, and ~700-fold selectivity for binding to KRAS^G12D as compared to KRAS^WT. MRTX1133 also demonstrated potent inhibition of activated KRAS^G12D based on biochemical and co-crystal structural analyses. MRTX1133 inhibited ERK1/2 phosphorylation and cell viability in KRAS^G12D-mutant cell lines, with median IC₅₀ values of ~5 nM, and demonstrated >1,000-fold selectivity compared to KRAS^WT cell lines. MRTX1133 exhibited dose-dependent inhibition of KRAS-mediated signal transduction and marked tumor regression (≥30%) in a subset of KRAS^G12D-mutant cell-line-derived and patient-derived xenograft models, including eight of 11 (73%) pancreatic ductal adenocarcinoma (PDAC) models. Pharmacological and CRISPR-based screens demonstrated that co-targeting KRAS^G12D with putative feedback or bypass pathways, including EGFR or PI3Kα, led to enhanced anti-tumor activity. Together, these data indicate the feasibility of selectively targeting KRAS mutants with non-covalent, high-affinity small molecules and illustrate the therapeutic susceptibility and broad dependence of KRAS^G12D mutation-positive tumors on mutant KRAS for tumor cell growth and survival.

Utilizing mast cells in a positive manner to overcome inflammatory and allergic diseases

Mast cells (MCs) are immune cells widely distributed in the body, accompanied by diverse phenotypes and functions. Committed mast cell precursors (MCPs) leave the bone marrow and enter the blood circulation, homing to peripheral sites under the control of various molecules from different microenvironments, where they eventually differentiate and mature. Partly attributable to the unique maturation mechanism, MCs display high functional heterogeneity and potentially plastic phenotypes. High plasticity also means that MCs can exhibit different subtypes to cope with different microenvironments, which we call “the peripheral immune education system”. Under the peripheral immune education system, MCs showed a new character from previous cognition in some cases, namely regulation of allergy and inflammation. In this review, we focus on the mucosal tissues, such as the gastrointestinal tract, to gain insights into the mechanism underlying the migration of MCs to the gut or other organs and their heterogeneity, which is driven by different microenvironments. In particular, the immunosuppressive properties of MCs let us consider that positively utilizing MCs may be a new way to overcome inflammatory and allergic disorders.

Engaging innate immunity for targeting the epidermal growth factor receptor: Therapeutic options leveraging innate immunity versus adaptive immunity versus inhibition of signaling

The epidermal growth factor receptor (EGFR) is a key player in the normal tissue physiology and the pathology of cancer. Therapeutic approaches have now been developed to target oncogenic genetic aberrations of EGFR, found in a subset of tumors, and to take advantage of overexpression of EGFR in tumors. The development of small-molecule inhibitors and anti-EGFR antibodies targeting EGFR activation have resulted in effective but limited treatment options for patients with mutated or wild-type EGFR-expressing cancers, while therapeutic approaches that deploy effectors of the adaptive or innate immune system are still undergoing development. This review discusses EGFR-targeting therapies acting through distinct molecular mechanisms to destroy EGFR-expressing cancer cells. The focus is on the successes and limitations of therapies targeting the activation of EGFR versus those that exploit the cytotoxic T cells and innate immune cells to target EGFR-expressing cancer cells. Moreover, we discuss alternative approaches that may have the potential to overcome limitations of current therapies; in particular the innate cell engagers are discussed. Furthermore, this review highlights the potential to combine innate cell engagers with immunotherapies, to maximize their effectiveness, or with unspecific cell therapies, to convert them into tumor-specific agents.

Real-world overall survival of patients receiving cetuximab in later lines of treatment for metastatic colorectal cancer

Aim: To examine characteristics of and treatment duration and real-world overall survival (rwOS) in patients receiving cetuximab as second-line (2L) or third-line (3L) treatment for metastatic colorectal cancer. Materials & methods: This was a retrospective study of 1096 and 684 patients in 2L and 3L cohorts, respectively. Results: The most common cetuximab-based regimens were cetuximab + folinic acid, fluorouracil and irinotecan (2L: 44%; 3L: 32%) and cetuximab + irinotecan (2L: 28%; 3L: 35%). Kaplan-Meier survival estimates and stepwise Cox regression model analysis demonstrated median treatment duration and rwOS of 3.7 and 14.4 months, respectively, in patients receiving treatment in the 2L cohort. In the 3L cohort, treatment duration was 3.3 months and rwOS was 12.0 months. Conclusion: This large real-world study provides evidence of rwOS in patients with metastatic colorectal cancer receiving cetuximab-based regimens as 2L or 3L treatment.

HER2 and HER3 as Therapeutic Targets in Head and Neck Cancer

ABSTRACT

Work over the past several decades has identified that aberrations in the ErbB signaling pathways are key drivers of oncogenesis, and concurrent efforts to discover targetable vulnerabilities to counter this aberrant oncogenic signaling offer tremendous promise in treating a host of human cancers. These efforts have been centered primarily on EGFR (also known as HER1), leading to the discovery of the first targeted therapies approved for head and neck cancer. More recently, HER2 and HER3 signaling pathways have been identified as highly dysregulated in head and neck cancer. This review highlights the HER2 and HER3 signaling pathways and clinical efforts to target these receptors and their aberrant signaling to treat head and neck squamous cell carcinomas and other head and neck malignancies, including salivary gland carcinomas. This includes the use of small molecule inhibitors and blocking antibodies, both as single agents or as part of multimodal precision targeted and immunotherapies.

Identification of hub genes related to CD4+ memory T cell infiltration with gene co-expression network predicts prognosis and immunotherapy effect in colon adenocarcinoma

Background: CD4+ memory T cells (CD4+ MTCs), as an important part of the microenvironment affecting tumorigenesis and progression, have rarely been systematically analyzed. Our purpose was to comprehensively analyze the effect of CD4+ MTC infiltration on the prognosis of colon adenocarcinoma (COAD). Methods: Based on RNA-Seq data, weighted gene co-expression network analysis (WGCNA) was used to screen the CD4+ MTC infiltration genes most associated with colon cancer and then identify hub genes and construct a prognostic model using the least absolute shrinkage and selection operator algorithm (LASSO). Finally, survival analysis, immune efficacy analysis, and drug sensitivity analysis were performed to evaluate the role of the prognostic model in COAD. Results: We identified 929 differentially expressed genes (DEGs) associated with CD4+ MTCs and constructed a prognosis model based on five hub genes (F2RL2, TGFB2, DTNA, S1PR5, and MPP2) to predict overall survival (OS) in COAD. Kaplan-Meier analysis showed poor prognosis in the high-risk group, and the analysis of the hub gene showed that overexpression of TGFB2, DTNA, S1PR5, or MPP2 was associated with poor prognosis. Clinical prediction nomograms combining CD4+ MTC-related DEGs and clinical features were constructed to accurately predict OS and had high clinical application value. Immune efficacy and drug sensitivity analysis provide new insights for individualized treatment. Conclusion: We constructed a prognostic risk model to predict OS in COAD and analyzed the effects of risk score on immunotherapy efficacy or drug sensitivity. These studies have important clinical significance for individualized targeted therapy and prognosis.

Global research trends on precision cancer medicine-related rashes (2008-2021): A bibliographic study

Background

Precision cancer medicine-related rashes are a kind of skin and mucous lesions caused by precision therapy. More and more evidences indicated that such events should not be ignored in the course of anti-tumor therapy. Since cancer treatment entered the “Precision Era”, there has been a rapid increase in this field. However, there was few bibliometric studies to provide an overall review of this field. This study aims to evaluate the literature output and trends in researches on precision cancer medicine-related rashes from a global perspective.

Methods

Collected publications on precision cancer medicine-related rashes from the Web of Science Core Collection database, which were limited to articles and reviews in English. Microsoft Excel, VOS viewer and CiteSpace V were used for quantitative and visual analysis.

Results

A total of 1,229 papers were identified. From 2008 to 2021, annual publications increased year by year. The United States published the most papers in this field (44.9%) and ranking first in citation frequency (19,854 times) and H-index (69). The University of Texas system ranks first with 98 papers published. Lacouture M.E and Robert C were the principal investigators. Cancers has the largest number of articles published, with 70 articles. In recent years, there have been research hotspots related to immunotherapy, including ipilimumab, immunotherapy, tumor microenvironment, association, checkpoint inhibitor, and cutaneous adverse event.

Conclusion

Precision cancer medicine-related rashes are a hot research topic in oncology. The number of relevant publications will increase dramatically. “Checkpoint inhibitors”, “skin adverse events”, “associations” and “tumor microenvironment” may become research hotspots in the future.

Optimized scaling of translational factors in oncology: from xenografts to RECIST

Purpose

Tumor growth inhibition (TGI) models are regularly used to quantify the PK–PD relationship between drug concentration and in vivo efficacy in oncology. These models are typically calibrated with data from xenograft mice and before being used for clinical predictions, translational methods have to be applied. Currently, such methods are commonly based on replacing model components or scaling of model parameters. However, difficulties remain in how to accurately account for inter-species differences. Therefore, more research must be done before xenograft data can fully be utilized to predict clinical response.

Method

To contribute to this research, we have calibrated TGI models to xenograft data for three drug combinations using the nonlinear mixed effects framework. The models were translated by replacing mice exposure with human exposure and used to make predictions of clinical response. Furthermore, in search of a better way of translating these models, we estimated an optimal way of scaling model parameters given the available clinical data.

Results

The predictions were compared with clinical data and we found that clinical efficacy was overestimated. The estimated optimal scaling factors were similar to a standard allometric scaling exponent of − 0.25.

Conclusions

We believe that given more data, our methodology could contribute to increasing the translational capabilities of TGI models. More specifically, an appropriate translational method could be developed for drugs with the same mechanism of action, which would allow for all preclinical data to be leveraged for new drugs of the same class. This would ensure that fewer clinically inefficacious drugs are tested in clinical trials.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00280-022-04458-8.

Efficacy and safety of HER2-targeted inhibitors for metastatic colorectal cancer with HER2-amplified: A meta-analysis

OBJECTIVE

To systematically evaluate the efficacy and safety of human epidermal growth factor receptor 2 (HER2)-targeted inhibitors for metastatic colorectal cancer (mCRC) with HER2-amplified.

METHOD

A systematic search of PubMed, Embase, Cochrane Library, Wan fang, VIP, and the CNKI database was conducted for literature published up to 28 February 2022 on the use of HER2-targeted inhibitors in the treatment of HER2-amplified mCRC. The retrieved articles were screened to determine the final inclusion of literature and extract relevant data, including the objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and incidence of serious adverse events (SAEs) (grade ≥3AEs). In our study, we used merging ratios, means, and 95% confidence intervals (CIs) to describe the efficacy and safety of HER2-targeted inhibitors when treating HER2-amplified mCRC.

RESULTS

The meta-analysis included 8 single-arm clinical trials comprising 258 patients with HER2-amplified mCRC who received second-line or above treatment. In our meta-analysis of mCRC treated with HER2-targeted inhibitors, the ORR and DCR were respectively 29% (95% CI 20-40) and 71% (95% CI 63-78). The median PFS (mPFS) and median OS (mOS) were respectively 4.89 months (95% CI 3.82-5.97) and 13.04 months (95% CI 9.45-16.62). The incidence of SAEs was 12% (95% CI 3-25).

CONCLUSIONS

As the second-line or above treatment, HER2-targeted inhibitors have exhibited good antitumor efficacy and safety in HER2-amplified mCRC patients. Treatment patterns in clinically relevant subpopulations of mCRC patients can be possibly changed using HER2-targeted therapeutic strategies.

Cytokine- and chemokine-induced inflammatory colorectal tumor microenvironment: Emerging avenue for targeted therapy

Colorectal cancer (CRC) is a predominant life-threatening cancer, with liver and peritoneal metastases as the primary causes of death. Intestinal inflammation, a known CRC risk factor, nurtures a local inflammatory environment enriched with tumor cells, endothelial cells, immune cells, cancer-associated fibroblasts, immunosuppressive cells, and secretory growth factors. The complex interactions of aberrantly expressed cytokines, chemokines, growth factors, and matrix-remodeling enzymes promote CRC pathogenesis and evoke systemic responses that affect disease outcomes. Mounting evidence suggests that these cytokines and chemokines play a role in the progression of CRC through immunosuppression and modulation of the tumor microenvironment, which is partly achieved by the recruitment of immunosuppressive cells. These cells impart features such as cancer stem cell-like properties, drug resistance, invasion, and formation of the premetastatic niche in distant organs, promoting metastasis and aggressive CRC growth. A deeper understanding of the cytokine- and chemokine-mediated signaling networks that link tumor progression and metastasis will provide insights into the mechanistic details of disease aggressiveness and facilitate the development of novel therapeutics for CRC. Here, we summarized the current knowledge of cytokine- and chemokine-mediated crosstalk in the inflammatory tumor microenvironment, which drives immunosuppression, resistance to therapeutics, and metastasis during CRC progression. We also outlined the potential of this crosstalk as a novel therapeutic target for CRC. The major cytokine/chemokine pathways involved in cancer immunotherapy are also discussed in this review.

Biologics in rectal cancer

INTRODUCTION

Despite the use of multimodality therapy, locally advanced rectal cancer (LARC) still presents high rates of disease recurrence. Fluoropyrimidine-based chemotherapy concurrently with radiation therapy (RT) remains the cornerstone of neoadjuvant therapy of LARC, and novel therapies are urgently needed in order to improve the clinical outcomes.

AREAS COVERED

We aim to summarize data from completed and ongoing clinical trials addressing the role of biological therapies, including monoclonal antibodies, immune checkpoint inhibitors (ICIs), antibody-drug conjugates, bispecific antibodies, and gene therapies in the systemic therapy of rectal cancer.

EXPERT OPINION

Deeper understanding of the molecular biology of colorectal cancer (CRC) has allowed meaningful advances in the systemic therapy of metastatic disease in the past few years. The larger applicability of biological therapy in CRC, including genome-guided targeted therapy, antiangiogenics, and immunotherapy, gives us optimism for the personalized management of rectal cancer. Microsatellite instability (MSI) tumors have demonstrated high sensitivity to ICIs, and preliminary findings in the neoadjuvant setting of rectal cancer are promising. To date, antiangiogenic and anti-EGFR therapies in LARC have not demonstrated the same benefit seen in metastatic disease. The outstanding results accomplished by biomarker-guided therapy in metastatic CRC will guide future developments of biological therapy in LARC.

EGFR, HER2, and HER3 protein expression in paired primary tumor and lymph node metastasis of colorectal cancer

Due to the difficulty in sampling of metastatic tumors, patient selection is commonly based on results of primary tumor samples when metastatic samples are not available. However, due to tumor heterogeneity, metastatic tumors may be different from primary tumors in their phenotypes. The aim of this study was to investigate the expression of EGFR, HER2, and HER3 between primary and lymph node metastatic lesions of colorectal cancer. Paired primary tumors and lymph node metastases from 79 patients with colorectal cancer were retrospectively collected and analyzed for EGFR, HER2, and HER3 expression. High EGFR, HER2, and HER3 expression (2+ and 3+) was found in 64.2%, 66.0%, and 85.0% of primary tumors, and 56.8%, 46.0%, and 76.0% of lymph node metastases, respectively. Correlation rates between primary and metastatic lesions were 67.1%, 63.3%, and 74.7% for EGFR, HER2, and HER3, respectively. Stage IV tumors (with distant metastasis) had higher correlation rates of HER2 expression compared to stage III tumors (without distant metastasis) (P = 0.050). Moderate correlation rates in EGFR, HER2, and HER3 expression were observed between primary and metastatic lesions of colorectal cancer. Tumor stage or existence of distant metastasis could serve as potential predictive markers for the correlation of HER2 expression between primary tumors and lymph node metastases of colorectal cancer.

The first Middle East and North Africa expert consensus recommendations for the management of advanced colorectal cancer

Colorectal cancer (CRC) is ranked as the third most prevalent and the second deadliest cancer worldwide. In the Middle East and North Africa (MENA) region, the number of CRC cases increased over the past decades and will nearly double by 2030. The lack of clear MENA guidelines for the management of patients with CRC represents a step backwards in the fight against this burden. Therefore a panel of 24 MENA experts in the field of gastrointestinal oncology developed, using a Delphi process, the first consensus recommendations for the management of patients with advanced CRC. Forty-seven different statements were formulated in the areas of epidemiology, screening, biomarkers and treatment. These recommendations will guide, standardize and unify the management of this cancer in the MENA region.

Safety and tolerability of intravitreal cetuximab in young and adult rabbits

To assess safety and tolerability of intraocularly applied cetuximab as epidermal growth factor receptor antibody, we conducted the experimental study which consisted of groups of adult rabbits (body weight: 2.4 kg) and young rabbits (body weight: 1.6 kg). All animals received three intravitreal injections of 0.5 mg cetuximab (Erbitux) (0.10 mL; 5 mg cetuximab/mL) into their right eyes in 4-week intervals, while the contralateral eyes received intravitreal injections of Ringer's solution. All animals underwent regular ophthalmological examinations at baseline and two-week intervals. Four weeks after the last injection, the animals were sacrificed, and the eyes were enucleated, fixed and examined by light microscopy. The study included 10 adult rabbits (age: 18 weeks; range: 17–19 weeks) and 8 young rabbits (age: 8 weeks; range: 7–10 weeks). Biometric measurements of axial length, anterior chamber depth and lens thickness and intraocular pressure readings did not differ significantly (all P > 0.05, Bonferroni corrected) between the right (study) eyes and the left (control) eyes, neither in the young nor in the adult rabbit group. Signs of intraocular inflammation or fundus peculiarities were not detected. Thickness of the outer nuclear layer, inner nuclear layer, combined outer and inner nuclear layer and outer plexiform layer, and total retina, measured at the posterior pole, posterior pole/equator midpoint, equator, and ora serrata region, did not vary significantly between study eyes and control eyes (all P > 0.05, Bonferroni corrected). The results suggest that repeated intravitreal application of cetuximab did not result in any detected intraocular toxic or destructive effect in young and adult rabbits, concurring with the notion of an intraocular tolerability of cetuximab.

Plasma Protein Biomarkers in Advanced or Metastatic Colorectal Cancer Patients Receiving Chemotherapy With Bevacizumab or Cetuximab: Results from CALGB 80405 (Alliance)

PURPOSE

CALGB 80405 compared the combination of first-line chemotherapy with cetuximab or bevacizumab in the treatment of advanced or metastatic colorectal cancer (mCRC). Although similar clinical outcomes were observed in the cetuximab-chemotherapy group and the bevacizumab-chemotherapy group, biomarkers could identify patients deriving more benefit from either biologic agent.

PATIENTS AND METHODS

In this exploratory analysis, the Angiome, a panel of 24 soluble protein biomarkers were measured in baseline plasma samples in CALGB 80405. Prognostic biomarkers were determined using univariate Cox proportional hazards models. Predictive biomarkers were identified using multivariable Cox regression models including interaction between biomarker level and treatment.

RESULTS

In the total population, high plasma levels of Ang-2, CD73, HGF, ICAM-1, IL6, OPN, TIMP-1, TSP-2, VCAM-1, and VEGF-R3 were identified as prognostic of worse progression-free survival (PFS) and overall survival (OS). PlGF was identified as predictive of lack of PFS benefit from bevacizumab [bevacizumab HR, 1.51; 95% confidence interval (CI), 1.10-2.06; cetuximab HR, 0.94; 95% CI, 0.71-1.25; Pinteraction = 0.0298] in the combined FOLFIRI/FOLFOX regimens. High levels of VEGF-D were predictive of lack of PFS benefit from bevacizumab in patients receiving FOLFOX regimen only (FOLFOX/bevacizumab HR, 1.70; 95% CI, 1.19-2.42; FOLFOX/cetuximab HR, 0.92; 95% CI, 0.68-1.24; Pinteraction = 0.0097).

CONCLUSIONS

In this exploratory, hypothesis-generating analysis, the Angiome identified multiple prognostic biomarkers and two potential predictive biomarkers for patients with mCRC enrolled in CALGB 80405. PlGF and VEGF-D predicted lack of benefit from bevacizumab in a chemo-dependent manner. See related commentaries by Mishkin and Kohn, p. 2722 and George and Bertagnolli, p. 2725.

TKIs beyond immunotherapy predict improved survival in advanced HCC

PURPOSE

For patients with advanced HCC, predictors of immunotherapy response are scarce, and the benefits of tyrosine kinase inhibitor (TKI) treatment after immunotherapy are unclear. We explored whether clinical features, such as target lesion response, immune-mediated toxicity, or subsequent TKI therapy predict immunotherapy response.

METHODS

We retrospectively studied 77 patients with advanced HCC receiving immunotherapy. Patient characteristics and outcomes were assessed using various statistical methods, including the log-rank test and Kaplan-Meier methods. Cox proportional hazard modeling was used for multivariable survival analysis.

RESULTS

For all patients, median overall survival (mOS) was 13 months (95% CI 8-19), and median progression-free survival (mPFS) was 6 months (95% CI 4-10). Patients with partial response (PR) and stable disease (SD) compared to progressive disease (PD) had prolonged mPFS (27 vs. 5 vs. 1 month(s), p < 0.0001) and mOS (not met vs. 11 vs. 3 months, p < 0.0001). Patients with vs. without immune-mediated toxicities trended towards longer mPFS (9 vs. 4 months p = 0.133) and mOS (17 vs. 9 months; p = 0.095). Patients who did vs. did not receive a tyrosine kinase inhibitor (TKI) after immunotherapy had a significantly improved mOS (19 vs. 5 months, p = 0.0024)). Based on multivariate modeling, the hazard ratio (HR) of overall survival (OS) of patients receiving TKI vs. no TKI was 0.412 (p = 0.0043).

CONCLUSION

We show that disease control predicts prolonged mOS and mPFS. Furthermore, TKI therapy administered after immunotherapy predicts prolonged mOS in patients with advanced HCC.

Role of ErbB1 in the Underlying Mechanism of Lapatinib-Induced Diarrhoea: A Review

Lapatinib, an orally administered small-molecule tyrosine kinase inhibitor (SM-TKI), is an effective treatment for ErbB2-positive breast cancer. However, its efficacy as one of the targeted cancer therapies has been hampered by several adverse effects, especially gastrointestinal toxicity, commonly manifested as diarrhoea. Although it can be generally tolerated, diarrhoea is reported as the most common and most impactful on a patient's quality of life and associated with treatment interruption. Severe diarrhoea can result in malabsorption, leading to dehydration, fatigue, and even death. ErbB1 is an epidermal growth factor profoundly expressed in normal gut epithelium while lapatinib is a dual ErbB1/ErbB2 tyrosine kinase inhibitor. Thus, ErbB1 inhibition by lapatinib may affect gut homeostasis leading to diarrhoea. Nevertheless, the underlying mechanisms remain unclear. This review article provides evidence of the possible mechanisms of lapatinib-induced diarrhoea that may be related to/or modulated by ErbB1. Insight regarding the involvement of ErbB1 in the pathophysiological changes such as inflammation and intestinal permeability as the underlying cause of diarrhoea is covered in this article.

Emerging trends in immunotoxin targeting cancer stem cells

Cancer stem cells (CSCs) are self-renewing multipotent cells that play a vital role in the development of cancer drug resistance conditions. Various therapies like conventional, targeted, and radiotherapies have been broadly used in targeting and killing these CSCs. Among these, targeted therapy selectively targets CSCs and leads to overcoming disease recurrence conditions in cancer patients. Immunotoxins (ITs) are protein-based therapeutics with selective targeting capabilities. These chimeric molecules are composed of two functional moieties, i.e., a targeting moiety for cell surface binding and a toxin moiety that induces the programmed cell death upon internalization. Several ITs have been constructed recently, and their preclinical and clinical efficacies have been evaluated. In this review, we comprehensively discussed the recent preclinical and clinical advances as well as significant challenges in ITs targeting CSCs, which might reduce the burden of drug resistance conditions in cancer patients from bench to bedside.

Depleting receptor tyrosine kinases EGFR and HER2 overcomes resistance to EGFR inhibitors in colorectal cancer

BACKGROUND

Epidermal growth factor receptor (EGFR) inhibitors, including cetuximab and panitumumab, are valuable therapeutics for colorectal cancer (CRC), but resistance to these inhibitors is common. The reason for such resistance is not well understood, which hampers development of better therapeutic strategies. Although activating mutations in KRAS, BRAF and PIK3CA are considered major drivers of CRC resistance to EGFR inhibitors, therapeutic targeting of these drug resistance drivers has not produced substantial clinical benefit.

METHODS

We exploited cell lines and mouse tumor models (cell line xenografts and patient derived xenografts) for experiments of genetic and pharmacologic depletion of EGFR and/or its family member HER2, including EGFR mutants, inhibition of EGFR ligand shedding, and biochemical analysis of signaling proteins, to delineate the mechanism of CRC resistance to EGFR inhibitors and to assess the therapeutic activity of PEPDG278D, which is a recombinant human protein that induces the degradation of both EGFR and HER2.

RESULTS

The sensitivity of CRC cells to cetuximab and panitumumab correlates with the ability of these drugs to induce EGFR downregulation. PEPDG278D strongly inhibits oncogenic signaling and growth of CRC cells by causing profound depletion of EGFR and HER2, regardless of activating mutations of KRAS, BRAF and PIK3CA. siRNA knockdown of EGFR or HER2 also inhibits CRC cells resistant to EGFR inhibitors. Tumors harboring mutated KRAS, BRAF and/or PIK3CA also overexpress EGFR ligands, further suggesting that EGFR signaling remains important to the tumors. While excessive tumor-generated high-affinity EGFR ligands block target engagement by PEPDG278D, aderbasib, an inhibitor of ADAM10 and ADAM17, enables PEPDG278D to exert strong antitumor activity by inhibiting ligand shedding. Moreover, adding fluorouracil, which is commonly used in CRC treatment, to the combination of PEPDG278D and aderbasib further enhances tumor inhibition.

CONCLUSIONS

Our study shows that CRC resistance to EGFR inhibitors results primarily from the inability of the inhibitors to downregulate their target and that a PEPDG278D-based combination treatment overcomes the resistance.

Survival and prognostic factors for postoperative primary appendiceal cancer: a retrospective cohort study based on the Surveillance, Epidemiology, and End Results database

BACKGROUND

The factors affecting the postoperative survival of patients with primary appendiceal cancer (PAC) have yet to be fully explored. And there are no clear guidelines for adjuvant treatment after appendectomy. Whether chemotherapy can prolong patient survival after appendectomy, is critical in guiding postoperative medications. The majority of studies on appendiceal cancer are single case reports, and they focused on the incidence of appendiceal cancer. The present study aimed to investigate the survival characteristics of patients with primary appendiceal cancer after surgery using the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

The data of 2,891 cases of primary appendiceal cancer between 2004 to 2015 were obtained from the SEER database and subjected to survival analysis using the Kaplan-Meier method and Cox proportional-hazards model. The annual percentage change (APC) was calculated using the weighted least squares method.

RESULTS

The overall age-adjusted incidence rate per 100,000 population steadily increased from 0.58 in 2004 to 1.63 in 2015. For patients who received chemotherapy, the median overall survival (OS) was 65 months and the 5-year OS rate was 51.9%, and for patients who did not receive chemotherapy or whose chemotherapy status was unknown, the median OS was not reached and the 5-year OS rate was 78.9%. Age [35< age <69: hazard radio (HR) =2.147; 95% confidence interval (CI): 1.442-3.197, P<0.001; age >69: HR =5.259; 95% CI: 3.485-7.937, P<0.001], race (White race: HR =0.728; 95% CI: 0.590-0.899, P=0.003), histologic type (mucinous neoplasm: HR =0.690; 95% CI: 0.580-0.821, P<0.001; malignant carcinoid: HR =0.657; 95% CI: 0.536-0.806, P<0.001), grade (II: HR =1.794; 95% CI: 1.471-2.187, P<0.001; III: HR =2.905; 95% CI: 2.318-3.640, P<0.001; IV: HR =3.128; 95% CI: 2.159-4.533, P<0.001), and stage (localized: HR =0.236; 95% CI: 0.194-0.287, P<0.001; regional: HR =0.425; 95% CI: 0.362-0.499, P<0.001) were identified as independent predictors of survival. And after adjusting for known factors (age, sex, race, tumor size, marital status, histologic type, grade, stage), chemotherapy (HR =1.220; 95% CI: 1.050-1.417, P=0.009) was revealed to be an independent indicator of poor prognosis.

CONCLUSIONS

There was an increasing trend in the incidence of appendiceal cancer in the United States between 2004 and 2015. Chemotherapy was revealed to be an independent indicator of poor prognosis, which provide valuable insight into the therapy of primary appendiceal cancer. Large clinical trials of chemotherapy and targeted therapy for appendiceal cancer are urgently needed.

Antibody-Incorporated Nanomedicines for Cancer Therapy

Antibody-based cancer therapy, one of the most significant therapeutic strategies, has achieved considerable success and progress over the past decades. Nevertheless, obstacles including limited tumor penetration, short circulation half-lives, undesired immunogenicity, and off-target side effects remain to be overcome for the antibody-based cancer treatment. Owing to the rapid development of nanotechnology, antibody-containing nanomedicines that have been extensively explored to overcome these obstacles have already demonstrated enhanced anticancer efficacy and clinical translation potential. This review intends to offer an overview of the advancements of antibody-incorporated nanoparticulate systems in cancer treatment, together with the nontrivial challenges faced by these next-generation nanomedicines. Diverse strategies of antibody immobilization, formats of antibodies, types of cancer-associated antigens, and anticancer mechanisms of antibody-containing nanomedicines are provided and discussed in this review, with an emphasis on the latest applications. The current limitations and future research directions on antibody-containing nanomedicines are also discussed from different perspectives to provide new insights into the construction of anticancer nanomedicines.

Cellular irinotecan resistance in colorectal cancer and overcoming irinotecan refractoriness through various combination trials including DNA methyltransferase inhibitors: a review

Treatment with pharmacological drugs for colorectal cancer (CRC) remains unsatisfactory. A major cause of failure in pharmacotherapy is the resistance of colon cancer cells to the drugs, creating an urgent issue. In this review, we summarize previous studies on the resistance of CRC cells to irinotecan and discuss possible reasons for refractoriness. Our review presents the following five major causes of irinotecan resistance in human CRC: (1) cellular irinotecan resistance is induced mainly through the increased expression of the drug efflux transporter, ABCG2; (2) cellular irinotecan resistance is also induced in association with a nuclear receptor, pregnane/steroid X receptor (PXR/SXR), which is enriched in the CYP3A4 gene enhancer region in CRC cells by exposing the cells to SN-38; (3) irinotecan-resistant cells possess either reduced DNA topoisomerase I (Top1) expression at both the mRNA and protein levels or Top1 missense mutations; (4) alterations in the tumor microenvironment lead to drug resistance through intercellular vesicle-mediated transmission of miRNAs; and (5) CRC stem cells are the most difficult targets to successfully treat CRC. In the clinical setting, CRC gradually develops resistance to initially effective irinotecan-based therapy. To solve this problem, several clinical trials, such as irinotecan plus cetuximab vs. cetuximab monotherapy, have been conducted. Another clinical trial on irinotecan plus guadecitabine, a DNA-methyltransferase inhibitor, has also been conducted.

Efficacy and Safety of Cetuximab Dosing (biweekly vs weekly) in Patients with KRAS Wild-type Metastatic Colorectal Cancer: A Meta-analysis

BACKGROUND

Cetuximab 500 mg/m2 biweekly (Q2W) plus chemotherapy is commonly used and recommended by NCCN guidelines. This meta-analysis compares efficacy and safety between Q2W versus weekly (Q1W) cetuximab dosing.

METHODS

A systematic literature review was performed on Pubmed and RightFind (2007-2017) for patients with KRAS wild-type mCRC who received Q2W or Q1W cetuximab and other treatments. Observational studies and case reports were excluded. Randomized trials comparing Q2W and Q1W dosing, and single-arm trials with only Q2W schedule were included. CRYSTAL, a phase 3 randomized study with Q1W cetuximab dosing was paired with each single-arm study with a Q2W schedule and reweighted to achieve similar demographic/baseline characteristics. Overall survival (OS) and progression-free survival (PFS) with hazard ratios (HR), overall response rate (ORR) with odds ratios, and risk difference of adverse events of special interest (AESI) between Q2W versus Q1W cetuximab were analyzed.

RESULTS

Five phase 2 studies with cetuximab Q2W/Q1W dosing schedules were identified: CECOG (phase 2; Q2W, n = 77; Q1W, n = 75), NORDIC 7.5 (phase 2; Q2W, n = 152) and NORDIC 7 (arm C of phase 3; Q1W, n = 109), CELINE (n = 60), OPTIMIX (n = 99), and APEC (n = 289) all phase 2, Q2W, single-arm studies paired with CRYSTAL Q1W dosing (n = 303). Efficacy was similar between Q2W versus Q1W administration; OS HR = 0.96, 95% confidence interval (CI) [0.89, 1.04]; PFS HR = 0.96, 95% CI [0.87, 1.05]; ORR odds ratio 1.16, 95% CI [0.96, 1.41]. Mean differences (Q2W-Q1W) across AESI rates were not clinically meaningful with no obvious directionality.

CONCLUSION

This meta-analysis demonstrated no significant differences in efficacy and safety between Q2W versus Q1W cetuximab administration in mCRC patients.

MiR-31-3p do not predict anti-EGFR efficacy in first-line therapy of RAS wild-type metastatic right-sided colon cancer

BACKGROUND

Low miR-31-3p expression was identified as predictive of anti-EGFR efficacy in RAS-wt mCRC. Primary tumor side was also proposed as a predictive factor of anti-EGFR benefit. This retrospective multicentric study evaluated the predictive role of miR-31-3p in right-sided RAS-wt mCRC patients treated with first-line CT+anti-EGFR or CT+bevacizumab (Beva).

METHODS

Seventy-two right-sided RAS-wt mCRC patients treated in first-line with CT+anti-EGFR (n = 43) or Beva (n = 29) were included. Overall survival (OS), progression-free survival (PFS) and response rate (RR) were analyzed and stratified according to tumor miR-31-3p expression level and targeted therapy (TT).

RESULTS

BRAF V600E mutation was more frequent in high vs low miR-31-3p expressers (60.6% vs 15.4%, P < 0.001). PFS was significantly longer with CT+Beva than with CT+anti-EGFR (13 vs 7 months; P = 0.024). Among low miR-31-3p expressers, PFS, OS and RR were not significantly different between the two groups, while in high miR-31-3p expressers, only PFS was longer in the CT+Beva group (11 vs 6 months; P = 0.03). In patients treated with CT+anti-EGFR, low miR-31-3p expressers had a significantly longer OS (20 vs 13 months; P = 0.02) than high miR-31-3p expressers. ORR was not significantly different between the two groups of treatment, in both low and high miR-31-3p expressers. MiR-31-3p expression status was statistically correlated between primary tumors and corresponding metastases.

CONCLUSION

In this study, miR-31-3p couldn't identify a subgroup of patients with right-sided RAS-wt mCRC who might benefit from anti-EGFR and suggest that Beva is the TT of choice in first-line treatment of these patients.

The HER family as therapeutic targets in colorectal cancer

The human epidermal growth factor receptor (HER, ErbB) family has four members, epidermal growth factor receptor (EGFR), HER2, HER3, and HER4. Although distinct in ligands and functions, all of the HER family members are receptor tyrosine kinases playing important roles in the pathogenesis of cancers. In the era of precision medicine, the HER family is one of the most important and successful cancer therapeutic targets, hallmarked by the approval of anti-EGFR therapies for the treatment of colorectal cancer and non-small cell lung cancer, and anti-HER2 therapies for the treatment of breast cancer and gastric cancer. This review briefly discusses how HER family members were discovered, their functions and roles in cancer, and most importantly, the developmental history and recent updates of therapies targeting HER family members, with colorectal cancer as a focus. We also discussed the patient selection and drug resistance to anti-EGFR therapies in the treatment of colorectal cancer.

Therapeutic approaches for the treatment of head and neck squamous cell carcinoma-An update on clinical trials

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common non-skin cancer with a tobacco consumption and infection with high-risk human papillomavirus (HPV) being major risk factors. Despite advances in numerous therapy modalities, survival rates for HNSCC have not improved considerably; a vast number of clinical outcomes have demonstrated that a combination strategy (the most well-known docetaxel, cisplatin, and 5-fluorouracil) is the most effective treatment choice. Immunotherapy that targets immunological checkpoints is being tested in a number of clinical trials, either alone or in conjunction with chemotherapeutic or targeted therapeutic drugs. Various monoclonal antibodies, such as cetuximab and bevacizumab, which target the EGFR and VEGFR, respectively, as well as other signaling pathway inhibitors, such as temsirolimus and rapamycin, are also being studied for the treatment of HNSCC. We have reviewed the primary targets in active clinical studies in this study, with a particular focus on the medications and drug targets used.

Bioluminescent RAPPID Sensors for the Single-Step Detection of Soluble Axl and Multiplex Analysis of Cell Surface Cancer Biomarkers

Early diagnosis of cancer is essential for the efficacy of treatment. Our group recently developed RAPPID, a bioluminescent immunoassay platform capable of measuring a wide panel of biomarkers directly in solution. Here, we developed and systematically screened different RAPPID sensors for sensitive detection of the soluble fraction of Axl (sAxl), a cell surface receptor that is overexpressed in several types of cancer. The best-performing RAPPID sensor, with a limit of detection of 8 pM and a >9-fold maximal change in emission ratio, was applied to measure Axl in three different contexts: clinically relevant sAxl levels (∼0.5 and ∼1 nM) in diluted blood plasma, proteolytically cleaved Axl in the cell culture medium of A431 and HeLa cancer cells, and Axl on the membrane of A431 cells. We further extended the sensor toolbox by developing dual-color RAPPID for simultaneous detection of Axl and EGFR on A431 and HeLa cells, as well as an AND-gate RAPPID that measures the concurrent presence of these two cell surface receptors on the same cell. These new RAPPID sensors provide attractive alternatives for more laborious protein detection and quantification methods such as FACS and immunostainings, due to their simple practical implantation and low intrinsic background signal.

Near-Infrared Fluorescence Imaging of EGFR-Overexpressing Tumors in the Mouse Xenograft Model Using scFv-IRDye800CW and Cetuximab-IRDye800CW

EGFR (epidermal growth factor receptor) is overexpressed in a variety of human cancers (including squamous cell carcinoma of head and neck, colon cancer, and some breast cancers) and therefore is regarded as an ideal target for cancer therapy or imaging purposes. In the current study, we produced a scFv-based near-infrared probe (called cet.Hum.scFv-IRDye-800CW) and evaluated its ability in recognizing and imaging of EGFR-overexpressing tumors in a mouse model. Like the molecular probe consisting of its parental antibody (cetuximab, an FDA-approved monoclonal antibody) and IRD800CW, cet.Hum.scFv-IRDye-800CW was able to recognize EGFR-overexpressing tumors in mice. cet.Hum.scFv-IRDye-800CW was found to be superior to the cetuximab-based probe in imaging of mouse tumors. The tumor-to-background ratio and blood clearance rate were higher when cet.Hum.scFv-IRDye-800CW was used as an imaging probe.

Indications for conversion hepatectomy for initially unresectable colorectal cancer with liver metastasis

PURPOSE

Selected patients with initially unresectable colorectal cancer (CRC) and liver metastases undergo conversion surgery after appropriate chemotherapy. The prognosis of these patients is good, with some even cured of the disease. This retrospective, single-institution study analyzes the clinical importance of patient characteristics on the outcomes of conversion hepatectomy.

METHODS

We evaluated 229 consecutive patients with initially unresectable CRC and liver metastasis, who underwent systemic chemotherapy. The patients were assigned to groups depending on conversion hepatectomy.

RESULTS

Conversion hepatectomy was performed in 30 patients (13.1%). The proportion of patients with extrahepatic metastasis was significantly lower in the conversion group than in the unresectable group (30.0 vs. 66.8%; P < 0.01). The rate of left-sided primary colorectal tumors was significantly higher in the conversion group than in the unresectable group (96.7 vs. 65.8%; P < 0.01). Multivariate analyses identified that left-sided tumors, no extrahepatic metastasis, H1 or H2 grade CLM, and treatment with molecular-targeted agents were associated with conversion hepatectomy (odds ratios: 16.314, 4.216, 7.631, and 4.070; P < 0.01). Overall survival was significantly longer in the conversion group than in the unresectable group (MST: 50.0 versus 14.7 months; P < 0.01).

CONCLUSION

Left-sided primary tumors, absence of extrahepatic metastases, H1 or H2 grade, and use of molecular-targeted agents were associated with successful conversion hepatectomy; thus, patients with these characteristics may be candidates for conversion therapy.

Patient demographics and management landscape of metastatic colorectal cancer in the third-line setting: Real-world data in an australian population

BACKGROUND

Colorectal cancer is the third most common cancer and second leading cause of cancer mortality in Australia, thus carrying a significant disease burden.

AIMS

This analysis aims to explore real-world treatment landscape of metastatic colorectal cancer in the third-line setting.

METHODS

We retrospectively analysed treatment of recurrent and advanced colorectal cancer (TRACC) registry database from 2009 onwards. Patients treated with palliative intent who progressed after two lines of therapies were included. One treatment line was defined as any combination of systemic therapy given until progression.

RESULTS

Out of 1820 patients treated palliatively, 32% (590 patients) met study criteria. Of these, 43% (254 patients) proceeded to third-line therapy, equating to 14% of all metastatic patients. In KRAS mutant or unknown tumours (97 patients), fluoropyrimidine (FP)-oxaliplatin combination was the most common choice (51%), followed by FP-irinotecan (15%), trifluridine/tipiracil (11%), mono-chemotherapy (10%), regorafenib (5%) and others (7%). Majority of FP-doublet (83%) was given as rechallenge. In 157 patients with KRAS wildtype disease, monotherapy with EGFR inhibitor was most commonly used (41%), followed by EGFR inhibitor with chemotherapy (20%), FP-doublet (18%), mono-chemotherapy (6%), trifluridine/tipiracil (6%), regorafenib (1%) and others (8%). Median overall survival was 7.1 months (range 0.4-41.2), and median time on third-line treatment was 3 months (range 0.1-40).

CONCLUSIONS

In real-world Australian population, treatment choices differed based on KRAS status and will likely change with the availability of newer drugs on the pharmaceutical benefits scheme. Survival outcomes are comparable to newer agents in clinical trials for select patients.