Nanomedicine developments in the treatment of metastatic pancreatic cancer: focus on nanoliposomal irinotecan

Functional genomics reveals an off-target dependency of drug synergy in gastric cancer therapy

BACKGROUND

Integrating molecular-targeted agents into combination chemotherapy is transformative for enhancing treatment outcomes in cancer. However, realizing the full potential of this approach requires a clear comprehension of the genetic dependencies underlying drug synergy. While the interactions between conventional chemotherapeutics are well-explored, the interplay of molecular-targeted agents with conventional chemotherapeutics remains a frontier in cancer treatment. Hence, we leveraged a powerful functional genomics approach to decode genomic dependencies that drive synergy in molecular-targeted agent/chemotherapeutic combinations in gastric adenocarcinoma, addressing a critical need in gastric cancer therapy.

METHODS

We screened pharmacological interactions between fifteen molecular-targeted agent/conventional chemotherapeutic pairs in gastric adenocarcinoma cells, and examined the genome-scale genetic dependencies of synergy integrating genome-wide CRISPR screening with the shRNA-based signature assay. We validated the synergy in cell death using fluorescence-based and lysis-dependent inference of cell death kinetics assay, and validated the genetic dependencies by single-gene knockout experiments.

RESULTS

Our combination screen identified SN-38/erlotinib as the drug pair with the strongest synergism. Functional genomics assays unveiled a genetic dependency signature of SN-38/erlotinib identical to SN-38. Remarkably, the enhanced cell death with improved kinetics induced by SN-38/erlotinib was attributed to erlotinib's off-target effect, inhibiting ABCG2, rather than its on-target effect on EGFR.

CONCLUSION

In the era of precision medicine, where emphasis on primary drug targets prevails, our research challenges this paradigm by showcasing a robust synergy underpinned by an off-target dependency. Further dissection of the intricate genetic dependencies that underlie synergy can pave the way to developing more effective combination strategies in gastric cancer therapy.

New Frontiers in Pancreatic Cancer Management: Current Treatment Options and the Emerging Role of Neoadjuvant Therapy

Pancreatic ductal adenocarcinoma (PDAC) ranks among the 15 most prevalent cancers globally, characterized by aggressive growth and late-stage diagnosis. Advances in imaging and surgical techniques have redefined the classification of pancreatic PDAC into resectable, borderline resectable, and locally advanced pancreatic cancer. While surgery remains the most effective treatment, only 20% of patients are eligible at diagnosis, necessitating innovative strategies to improve outcomes. Therefore, traditional treatment paradigms, primarily surgical resection for eligible patients, are increasingly supplemented by neoadjuvant therapies (NAT), which include chemotherapy, radiotherapy, or a combination of both. By administering systemic therapy prior to surgery, NAT aims to reduce tumor size and increase the feasibility of complete surgical resection, thus enhancing overall survival rates and potentially allowing more patients to undergo curative surgeries. Recent advances in treatment protocols, such as FOLFIRINOX and gemcitabine-nab-paclitaxel, now integral to NAT strategies, have shown promising results in increasing the proportion of patients eligible for surgery by effectively reducing tumor size and addressing micrometastatic disease. Additionally, they offer improved response rates and survival benefits compared to traditional regimes. Despite these advancements, the role of NAT continues to evolve, necessitating ongoing research to optimize treatment regimens, minimize adverse effects, and identify patient populations that would benefit most from these approaches. Through a detailed analysis of current literature and recent clinical trials, this review highlights the transformative potential of NAT in managing PDAC, especially in patients with borderline resectable or locally advanced stages, promising a shift towards more personalized and effective management strategies for PDAC.

Synergism and attenuation of triptolide through prodrug engineering combined with liposomal scaffold strategy to enhance inhibition in pancreatic cancer

The prognosis of pancreatic cancer (PCa) is extremely poor because of its resistance to conventional therapies. Many previous studies have demonstrated that triptolide (TPL) has a potent tumoricidal activity on PCa. However, the clinical application of TPL in tumor therapy has been greatly limited by its poor aqueous solubility, short half-time, high toxicity and inefficient delivery. Here, through the engineering of prodrug technology combined with the nanodrug-delivery system (NDDS) strategy, we modified the main active site of TPL C14-OH by esterification reaction to obtain a highly lipophilic prodrug, and then encapsulated the drug in a phospholipid bilayer in liposomal vehicles through the thin-film hydration method for efficient delivery. A delivery system based on TPL lignocerate liposomes (TPL-LA-lip) for drug loading for targeted therapy against PCa was established. Our results showed that TPL-LA demonstrates exceptional compatibility with the phospholipid layer of liposomes, thereby enhancing drug retention in liposomal vehicle and improving tumor targeting and cellular uptake. Moreover, The system of TPL-LA-lip exhibited a sustained drug release profile in vitro, and intravenous administration significantly impedes tumor progression while reducing the toxicity of TPL in the PCa mouse model. These results demonstrated that the prodrug-loaded liposomes could significantly reduce the toxicity of TPL and enhance the biosafety. Overall, this prodrug approach is a simple and effective method to transform the highly toxic TPL into a safe and efficacious nanomedicine with excellent in vivo tolerability for PCa treatment.

Clinical outcomes of liposomal irinotecan in advanced pancreatic adenocarcinoma patients previously treated with conventional irinotecan-based chemotherapy: a real-world study

Background

The efficacy of combination chemotherapy beyond the first-line setting remains modest in patients with advanced pancreatic adenocarcinoma (PAC). Evidence from recent clinical studies has shown that liposomal irinotecan (nal-IRI) plus 5-fluorouracil (5-FU) and leucovorin (LV) resulted in survival benefits in patients with advanced pancreatic adenocarcinoma (APAC) after progression on gemcitabine-based treatment. However, the survival benefits of nal-IRI in the third and later lines, in which limited options are available, have yet to be extensively studied. Also, some studies have shown conflicting results regarding the impact of prior treatment with conventional IRI on patient outcomes following treatment with nal-IRI. Therefore, this real-world study aimed to evaluate the efficacy and safety of nal-IRI plus 5FU-LV in advanced PAC patients who progressed on conventional IRI-containing regimens.

Methods

A retrospective chart review was conducted between November 2016 to December 2022 on 30 patients diagnosed with advanced PAC who completed at least one cycle of nal-IRI plus 5-FU- LV and were previously treated with conventional IRI. Data regarding survival outcomes were retrieved.

Results

Thirty patients met the inclusion criteria. Overall, 76.7% of the patients received at least two lines of therapy prior to nal-IRI. The median overall duration of nal-IRI treatment was 2.0 months (IQR: 1.3 - 3.9 months). One patient (3.3%) had a partial response, and seven patients (23.3%) had stable disease as their best response. The median progression-free survival (PFS) was 1.9 months (95% CI 1.6 - 2.0) and the 6-month PFS rate was 20.0%. The median overall survival (OS) was 5.0 months (95% CI 3.4 - 7.0), and the 6-month OS rate was 36.7%. An interval between conventional IRI and nal-IRI ≥5.5 months was significantly associated with prolonged OS of 10.2 months (95% CI 3.3 - 12.1) versus 4.3 months (95% CI 2.1 - 5.9; p =0.003). Ten patients (33.3%) experienced grade 3 adverse events, most commonly nausea, fatigue, diarrhea, and non-neutropenic fever.

Conclusion

Nal-IRI plus 5FU/LV had modest survival benefits and an acceptable safety profile in patients with prior conventional IRI. A longer interval between conventional IRI and nal-IRI was associated with increased survival outcomes.

Revisiting the in-vitro and in-vivo considerations for in-silico modelling of complex injectable drug products

Complex injectable drug products (CIDPs) have often been developed to modulate the pharmacokinetics along with efficacy for therapeutic agents used for remediation of chronic disorders. The effective development of CIDPs has exhibited complex kinetics associated with multiphasic drug release from the prepared formulations. Consequently, predictability of pharmacokinetic modelling for such CIDPs has been difficult and there is need for advanced complex computational models for the establishment of accurate prediction models for in-vitro-in-vivo correlation (IVIVC). The computational modelling aims at supplementing the existing knowledge with mathematical equations to develop formulation strategies for generation of predictable and discriminatory IVIVC. Such an approach would help in reduction of the burden of effect of hidden factors on preclinical to clinical translations. Computational tools like physiologically based pharmacokinetics (PBPK) modelling have combined physicochemical and physiological properties along with IVIVC characteristics of clinically used formulations. Such techniques have helped in prediction and understanding of variability in pharmacodynamic parameters of potential generic products to clinically used formulations like Doxil®, Ambisome®, Abraxane® in healthy and diseased population using mathematical equations. The current review highlights the important formulation characteristics, in-vitro, preclinical in-vivo aspects which need to be considered while developing a stimulatory predictive PBPK model in establishment of an IVIVC and in-vitro-in-vivo relationship (IVIVR).

Liposomal Irinotecan Shows a Larger Therapeutic Index than Non-liposomal Irinotecan in Patient-Derived Xenograft Models of Pancreatic Cancer

INTRODUCTION

Liposomal irinotecan promotes controlled sustained release of irinotecan (CPT-11), therefore, we hypothesize that the therapeutic index (quantitative measurement of the relative efficacy/safety ratio of a drug) will be higher for liposomal than non-liposomal irinotecan.

METHODS

We compared the therapeutic indexes of liposomal and non-liposomal irinotecan in mice bearing subcutaneous patient-derived xenograft (PDX) pancreatic tumors under dosing regimens approximating the clinical setting. Following preliminary drug sensitivity/antitumor activity analyses on three PDX tumor models, one model was selected for analyses of efficacy, biomarker, toxicology, pharmacokinetics in mice receiving liposomal irinotecan (2.5, 10, 50 mg/kg/week) or non-liposomal irinotecan (10, 25, 50 mg/kg/week). The maximum tolerated dose (MTD) for each treatment was 50 mg/kg/week.

RESULTS

Using the selected IM-PAN-001 model at the MTD (both treatments, 50 mg/kg/week), antitumor activity, phospho-histone gamma-H2AX protein staining in cancer cell nuclei, histological tumor regression, and plasma levels of CPT-11 and its active metabolite SN-38 after 24 h were greater with liposomal than non-liposomal irinotecan, but tumor SN-38 levels were similar. At the lowest doses assessed, antitumor activity, histological tumor regression, and jejunum and bone marrow toxicity were similar. Based on these findings, liposomal and non-liposomal irinotecan had therapeutic indexes of 20 and 5, respectively.

CONCLUSION

This non-clinical study showed a fourfold broader therapeutic index with liposomal than non-liposomal irinotecan in mice bearing IM-PAN-001 PDX pancreatic tumors, even at optimal dosing for the two drugs. These findings support the clinical benefit observed with liposomal irinotecan in patients with pancreatic cancer.

PD-1/PD-L1 and DNA Damage Response in Cancer

The application of immunotherapy for cancer treatment is rapidly becoming more widespread. Immunotherapeutic agents are frequently combined with various types of treatments to obtain a more durable antitumor clinical response in patients who have developed resistance to monotherapy. Chemotherapeutic drugs that induce DNA damage and trigger DNA damage response (DDR) frequently induce an increase in the expression of the programmed death ligand-1 (PD-L1) that can be employed by cancer cells to avoid immune surveillance. PD-L1 exposed on cancer cells can in turn be targeted to re-establish the immune-reactive tumor microenvironment, which ultimately increases the tumor's susceptibility to combined therapies. Here we review the recent advances in how the DDR regulates PD-L1 expression and point out the effect of etoposide, irinotecan, and platinum compounds on the anti-tumor immune response.

Drug Stability and Minimized Acid-/Drug-Catalyzed Phospholipid Degradation in Liposomal Irinotecan

Therapeutics at or close to the nanoscale, such as liposomal irinotecan, offer significant promise for the treatment of solid tumors. Their potential advantage over the unencapsulated or free form of the drug is due in part to their altered biodistribution. For slow and sustained release, significant optimization of formulation is needed to achieve the required level of stability and allow long-term storage of the drug product. Gradient-based liposomal formulation of camptothecins such as irinotecan poses unique challenges owing to the camptothecin- and acid-catalyzed hydrolysis of phospholipid esters in the inner monolayer of the liposomal membrane. We demonstrated that a narrow set of conditions related to the external pH, temperature, intraliposomal concentration, identity of the drug-trapping agent, physical form of the drug inside the liposomes, and final drug load have a marked impact on the stability of the liposome phospholipid membrane. The physical form of the drug inside the liposome was shown to be an insoluble gel with an irinotecan-to-sulfate ratio approximating 1:1, reducing the potential for irinotecan-catalyzed phospholipid hydrolysis in the internal phospholipid monolayer. As a result of this work, a stable and active liposome formulation has been developed that maintains phospholipid chemical stability following long-term storage at 2-8°C.

A novel anti-tumor/anti-tumor-associated fibroblast/anti-mPEG tri-specific antibody to maximize the efficacy of mPEGylated nanomedicines against fibroblast-rich solid tumor

The therapeutic efficacy of methoxypolyethylene glycol (mPEG)-coated nanomedicines in solid tumor treatment is hindered by tumor-associated fibroblasts (TAFs), which promote tumor progression and form physical barriers. We developed an anti-HER2/anti-FAP/anti-mPEG tri-specific antibody (TsAb) for one-step conversion of mPEG-coated liposomal doxorubicin (Lipo-Dox) to immunoliposomes, which simultaneously target HER2⁺ breast cancer cells and FAP⁺ TAFs. The non-covalent modification did not adversely alter the physical characteristics and stability of Lipo-Dox. The TsAb-Lipo-Dox exhibited specific targeting and enhanced cytotoxicity against mono- and co-cultured HER2⁺ breast cancer cells and FAP⁺ TAFs, compared to bi-specific antibody (BsAb) modified or unmodified Lipo-Dox. An in vivo model of human breast tumor containing TAFs also revealed the improved tumor accumulation and therapeutic efficacy of TsAb-modified mPEGylated liposomes without signs of toxicity. Our data indicate that arming clinical mPEGylated nanomedicines with the TsAb is a feasible and applicable approach for overcoming the difficulties caused by TAFs in solid tumor treatment.

Nanomedicine in Pancreatic Cancer: Current Status and Future Opportunities for Overcoming Therapy Resistance

Simple Summary

Despite access to a vast arsenal of anticancer agents, many fail to realise their full therapeutic potential in clinical practice. One key determinant of this is the evolution of multifaceted resistance mechanisms within the tumour that may either pre-exist or develop during the course of therapy. This is particularly evident in pancreatic cancer, where limited responses to treatment underlie dismal survival rates, highlighting the urgent need for new therapeutic approaches. Here, we discuss the major features of pancreatic tumours that contribute to therapy resistance, and how they may be alleviated through exploitation of the mounting and exciting promise of nanomedicines; a unique collection of nanoscale platforms with tunable and multifunctional capabilities that have already elicited a widespread impact on cancer management.

Abstract

The development of drug resistance remains one of the greatest clinical oncology challenges that can radically dampen the prospect of achieving complete and durable tumour control. Efforts to mitigate drug resistance are therefore of utmost importance, and nanotechnology is rapidly emerging for its potential to overcome such issues. Studies have showcased the ability of nanomedicines to bypass drug efflux pumps, counteract immune suppression, serve as radioenhancers, correct metabolic disturbances and elicit numerous other effects that collectively alleviate various mechanisms of tumour resistance. Much of this progress can be attributed to the remarkable benefits that nanoparticles offer as drug delivery vehicles, such as improvements in pharmacokinetics, protection against degradation and spatiotemporally controlled release kinetics. These attributes provide scope for precision targeting of drugs to tumours that can enhance sensitivity to treatment and have formed the basis for the successful clinical translation of multiple nanoformulations to date. In this review, we focus on the longstanding reputation of pancreatic cancer as one of the most difficult-to-treat malignancies where resistance plays a dominant role in therapy failure. We outline the mechanisms that contribute to the treatment-refractory nature of these tumours, and how they may be effectively addressed by harnessing the unique capabilities of nanomedicines. Moreover, we include a brief perspective on the likely future direction of nanotechnology in pancreatic cancer, discussing how efforts to develop multidrug formulations will guide the field further towards a therapeutic solution for these highly intractable tumours.

Liposomal Irinotecan: A Review in Metastatic Pancreatic Adenocarcinoma

Liposomal irinotecan (nal-IRI; Onivyde^®; also known as pegylated liposomal irinotecan) has been developed with the aim of maximising anti-tumour efficacy while minimising drug-related toxicities compared with the conventional (non-liposomal) formulation of this topoisomerase 1 inhibitor. In combination with 5-fluorouracil and leucovorin (5-FU/LV), nal-IRI is the first agent to be specifically approved for use in patients with metastatic pancreatic ductal adenocarcinoma (mPDAC) who have progressed following gemcitabine-based therapy. In the pivotal, phase III NAPOLI-1 trial, intravenous administration of nal-IRI + 5-FU/LV to gemcitabine-pretreated patients with mPDAC (as a second-line treatment in approximately two-thirds of cases) was associated with a significant ≈ 2-month median overall survival advantage compared with 5-FU/LV alone. Moreover, adding nal-IRI to 5-FU/LV extended survival with a manageable safety profile and without adversely affecting health-related quality of life, thereby producing significant and clinically meaningful gains in quality-adjusted survival relative to 5-FU/LV alone. Complementing the observed efficacy and safety of nal-IRI in NAPOLI-1 are an increasing number of real-world studies, which provide evidence of the effectiveness of this combination therapy in the treatment of mPDAC that has progressed following gemcitabine-based therapy in contemporary clinical practice in Europe, the USA and East Asia. Thus, nal-IRI, in combination with 5-FU/LV, is the first regimen specifically approved for use as a second- or subsequent-line therapy in gemcitabine-pretreated patients with mPDAC and, as such, represents a valuable treatment option in this setting.

Axial pharmaceutical properties of liposome in cancer therapy: Recent advances and perspectives

Evaluation of axial properties including preparation, surface functionalization, and pharmacokinetics for delivery of pharmacologically active molecules and genes lead to pharmaceutical development of liposome in cancer therapy. Here, analysis of effects of the axial properties of liposome based on cancer treatment modalities as individually and coherently is vital and shows deserving further investigation for the future. In this review, recent progress in the analysis of preparation approaches, optimizing pharmacokinetic parameters, functionalization and targeting improvement and modulation of biological factors and components resulting in a better function of liposome in cancer for drug/gene delivery and immunotherapy are discussed. Here, recent developments on liposome with vaccines and immunoadjuvant carriers, and antigen-carrier system to cancer immunotherapy are introduced.

Combination Therapies and Drug Delivery Platforms in Combating Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC), the fourth leading cause of cancer-related death in the United States, is highly aggressive and resistant to both chemo- and radiotherapy. It remains one of the most difficult-to-treat cancers, not only due to its unique pathobiological features such as stroma-rich desmoplastic tumors surrounded by hypovascular and hypoperfused vessels limiting the transport of therapeutic agents, but also due to problematic early detection, which renders most treatment options largely ineffective, resulting in extensive metastasis. To elevate therapeutic effectiveness of treatments and overt their toxicity, significant enthusiasm was generated to exploit new strategies for combating PDAC. Combination therapy targeting different barriers to mitigate delivery issues and reduce tumor recurrence and metastasis has demonstrated optimal outcomes in patients' survival and quality of life, providing possible approaches to overcome therapeutic challenges. This paper aims to provide an overview of currently explored multimodal therapies using either conventional therapy or nanomedicines along with rationale, up-to-date progress, as well as the key challenges that must be overcome. Understanding the future directions of the field may assist in the successful development of novel treatment strategies for enhancing therapeutic efficacy in PDAC.

An imaging-based review of systemic therapies and associated toxicities in metastatic pancreatic cancer as per the 2018 ASCO guidelines: what every radiologist should know

OBJECTIVE

To provide an overview of what radiologists should know about systemic agents utilized in the modern treatment of metastatic pancreatic cancer and their associated toxicities.

RESULTS

The clinical landscape of metastatic pancreatic cancer has significantly evolved in recent years, with the advent of new first- and second-line systemic therapies. As these systemic treatment options continue to expand, knowledge of their clinically relevant features is becoming critical for radiologists. While the issues of surgical resectability and tumor response evaluation of advanced stages of pancreatic cancer have been thoroughly discussed in the radiology literature, the diagnostic importance of systemic therapies has tended to be less well appreciated. In this review, we provide a primer for radiologists outlining the radiologically pertinent features of modern systemic therapies used in the treatment of metastatic pancreatic ductal adenocarcinoma. These systemic agents are discussed from the standpoint of the newly updated 2018 ( https://doi.org/10.1007/s00261-019-01954-z ) guidelines for the treatment of metastatic pancreatic cancer from the American Society of Clinical Oncology (ASCO). Understanding the radiology relevance of these modern therapeutic agents is critical, especially with regard to treatment response and toxicity assessment.

CONCLUSION

Knowledge of the modern systemic therapies utilized in the treatment of metastatic pancreatic cancer and their associated toxicity profiles is critical in diagnostic imaging interpretation.

NAPOLI-1 phase 3 study of liposomal irinotecan in metastatic pancreatic cancer: Final overall survival analysis and characteristics of long-term survivors

BACKGROUND

Liposomal irinotecan (nal-IRI) plus 5-fluorouracil and leucovorin (5-FU/LV) is approved for patients with metastatic pancreatic ductal adenocarcinoma (mPDAC) previously treated with gemcitabine-based therapy. This approval was based on significantly improved median overall survival compared with 5-FU/LV alone (6.1 vs 4.2 months; hazard ratio [HR], 0.67) in the global phase 3 NAPOLI-1 trial. Here, we report the final survival analysis and baseline characteristics associated with long-term survivors (survival of ≥1 year) in the NAPOLI-1 trial.

PATIENTS AND METHODS

Patients with mPDAC were randomised to receive nal-IRI + 5-FU/LV (n = 117), nal-IRI (n = 151), or 5-FU/LV (n = 149) for the first 4 weeks of 6-week cycles. Baseline characteristics and efficacy in the overall population were compared with those in patients who survived ≥1 year. Through 16th November 2015, 382 overall survival events had occurred.

RESULTS

The overall survival advantage for nal-IRI+5-FU/LV vs 5-FU/LV was maintained from the original nanoliposomal irinotecan with fluorouracil and folinic acid in metastatic pancreatic cancer after previous gemcitabine-based therapy (NAPOLI-1) analysis (6.2 vs 4.2 months, respectively; HR, 0.75; 95% confidence interval: 0.57-0.99). Median progression-free survival, objective response rate and disease control rate also favoured nal-IRI+5-FU/LV therapy. Estimated one-year overall survival rates were 26% with nal-IRI+5-FU/LV and 16% with 5-FU/LV. Baseline characteristics associated with long-term survival in the nal-IRI+5-FU/LV arm were Karnofsky performance status ≥90, age ≤65 years, lower CA19-9 levels, neutrophil-to-lymphocyte ratio ≤5 and no liver metastases. No new safety concerns were detected.

CONCLUSIONS

The survival benefits of nal-IRI+5-FU/LV versus 5-FU/LV were maintained over an extended follow-up, and prognostic markers of survival ≥1 year were identified.

CLINICAL TRIAL REGISTRATION NUMBER

NCT01494506.

Status and future directions in the management of pancreatic cancer: potential impact of nanotechnology

Pancreatic ductal adenocarcinoma (PDAC) is typically diagnosed at a late stage, has limited treatments, and patients have poor survival rates. It currently ranks as the seventh leading cause of cancer deaths globally and has increasing rates of diagnosis. Improved PDAC treatment requires the development of innovative, effective, and economical therapeutic drugs. The late stage diagnosis limits options for surgical resection, and traditional PDAC chemotherapeutics correlate with increased organ and hematologic toxicity. In addition, PDAC tumor tissue is dense and highly resistant to many traditional chemotherapeutic applications, making the disease difficult to treat and impeding options for palliative care. New developments in nanotechnology may offer innovative options for targeted PDAC therapeutic drug delivery. Nanotechnology can be implemented using multimodality methods that offer increased opportunities for earlier diagnosis, precision enhanced imaging, targeted long-term tumor surveillance, and controlled drug delivery, as well as improved palliative care and patient comfort. Nanoscale delivery methods have demonstrated the capacity to infiltrate the dense, fibrous tumor tissue associated with PDAC, increasing delivery and effectiveness of chemotherapeutic agents and reducing toxicity through the loading of multiple drug therapies on a single nano delivery vehicle. This review presents an overview of nanoscale drug delivery systems and multimodality carriers at the forefront of new PDAC treatments.

Role of Inflammasomes in the Development of Gastrointestinal Diseases

Many diseases of the gastrointestinal tract have been attributed to chronic inflammation, and a few have identified the role of inflammasomes in their pathogenesis. Inflammasomes are a group of protein complexes comprising of several intracellular proteins that link the sensing of microbial products and metabolic stress to the proteolytic activation of the proinflammatory cytokines. Recent studies have implicated activation of several families of NOD-like receptors (NLRs) which are major components of inflammasomes in the development and exacerbation of many diseases of human systems. In this chapter, we discuss the role of inflammasomes in some of the most prevalent diseases of the gastrointestinal tract and highlight potential targets for treatment.

Potential applications and human biosafety of nanomaterials used in nanomedicine

With the rapid development of nanotechnology, potential applications of nanomaterials in medicine have been widely researched in recent years. Nanomaterials themselves can be used as image agents or therapeutic drugs, and for drug and gene delivery, biological devices, nanoelectronic biosensors or molecular nanotechnology. As the composition, morphology, chemical properties, implant sites as well as potential applications become more and more complex, human biosafety of nanomaterials for clinical use has become a major concern. If nanoparticles accumulate in the human body or interact with the body molecules or chemical components, health risks may also occur. Accordingly, the unique chemical and physical properties, potential applications in medical fields, as well as human biosafety in clinical trials are reviewed in this study. Finally, this article tries to give some suggestions for future work in nanomedicine research. Copyright © 2017 John Wiley & Sons, Ltd.

Update on the role of nanoliposomal irinotecan in the treatment of metastatic pancreatic cancer

Median survival for patients with metastatic pancreatic cancer (MPC) treated with combination chemotherapeutic agents such as gemcitabine-based regimens and FOLFIRINOX is currently less than 12 months. This highlights the need for more efficacious first-line, as well as second-line therapies. Nanoliposomal irinotecan, in combination with 5-fluorouracil (5-FU)/folinic acid has recently been assessed as second-line therapy after initial gemcitabine-based therapy. It is the first, second-line treatment approved by the US Food and Drug Administration to treat patients with MPC based on results of the NAnoliPOsomaL Irinotecan (NAPOLI-1) study, which showed that this regimen significantly prolonged progression-free survival (3.1 months versus 1.5 months) and overall survival (6.2 months versus 4.1 months) compared with 5-FU/folinic acid alone. In addition, this study also represented an important step forward in improving the efficacy of previously used chemotherapeutic agents by using nanoformulation to extend pharmacokinetic advantages such as slow clearance, low steady-state volume of distribution, and longer half-life. However, certain adverse effects that are seen more frequently with nanoliposomal irinotecan and 5-FU/folinic acid, compared with 5-FU/folinic acid alone, include neutropenia, fatigue, diarrhea, and nausea/vomiting. This merits close monitoring of patients who are on this combination, since these adverse events may necessitate dose reductions and growth factor support. It is imperative to check UGT1A1 gene status in all patients being considered for treatment with nanoliposomal irinotecan. Patients found to be homozygous for the UGT1A1*28 gene need to be started on a lower initial dose. As we gain more data with clinical use, we anticipate further characterization of the aforementioned toxicities in patients with UGT1A1 gene polymorphisms and other genetic variants.

Liposomal Irinotecan: A Review in Metastatic Pancreatic Adenocarcinoma

Intravenous liposomal irinotecan injection (Onivyde®) is approved for use in combination with 5-fluorouracil and leucovorin (5-FU/LV) in patients with metastatic pancreatic adenocarcinoma that has progressed following gemcitabine-based therapy. Liposomal irinotecan is a liposome-encapsulated formulation of the topoisomerase-1 inhibitor irinotecan, developed to overcome the pharmacological and clinical limitations of non-liposomal irinotecan. In the pivotal multinational, phase III NAPOLI-1 trial in patients with metastatic pancreatic adenocarcinoma that had progressed following gemcitabine-based therapy, liposomal irinotecan in combination with 5-FU/LV significantly prolonged median overall survival (OS; primary endpoint) and median progression-free survival (PFS) at the time of the primary analysis (after 313 events) and final analysis (after 382 events) compared with 5-FU/LV control therapy. The objective response rate was also significantly higher in the liposomal irinotecan plus 5-FU/LV group than in the control group. Liposomal irinotecan-based combination therapy had a manageable safety profile; the most common treatment-emergent adverse events (TEAEs) of grade ≥3 severity were haematological or gastrointestinal in nature. The incidence of neutropenic sepsis was low. In a setting where there is a paucity of second-line treatment options, liposomal irinotecan in combination with 5-FU/LV is an important emerging treatment option for metastatic adenocarcinoma of the pancreas that has progressed following gemcitabine-based therapy.

The long story of camptothecin: From traditional medicine to drugs

20-(S)-Camptothecin (CPT) is a natural alkaloid extracted from the bark of Camptotheca acuminata (Chinese happy tree). It acts as a DNA topoisomerase 1 poison with an interesting antitumor activity and its use is limited by low stability and solubility and unpredictable drug-drug interactions. Since the late 20th century, it has been widely used in cancer therapy and, since extraction yields from plant tissues are very low, various synthetic routes have been developed to satisfy the increase in demand for CPT. Moreover, SAR studies have allowed for the development of more potent CPT analogues topotecan and irinotecan. Unfortunately, resistance has already occurred in several tumour lines. Additional studies are needed to better understand the relationship between substituents and resistance, its clinical relevance and the impact of related gene polymorphism. One of the latest research approaches focuses on modifying the delivery mode to improve tumour cell uptake and reduce toxicity.

Interventional Nanotheranostics of Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) accounts for over 90% of all pancreatic cancer. Nanoparticles (NPs) offer new opportunities for image-guided therapy owing to the unique physicochemical properties of the nanoscale effect and the multifunctional capabilities of NPs. However, major obstacles exist for NP-mediated cancer theranostics, especially in PDAC. The hypovascular nature of PDAC may impede the deposition of NPs into the tumor after systemic administration, and most NPs localize predominantly in the mononuclear phagocytic system, leading to a relatively poor tumor-to-surrounding-organ uptake ratio. Image guidance combined with minimally invasive interventional procedures may help circumvent these barriers to poor drug delivery of NPs in PDAC. Interventional treatments allow regional drug delivery, targeted vascular embolization, direct tumor ablation, and the possibility of disrupting the stromal barrier of PDAC. Interventional treatments also have potentially fewer complications, faster recovery, and lower cost compared with conventional therapies. This work is an overview of current image-guided interventional cancer nanotheranostics with specific attention given to their applications for the management of PDAC.