Enhancing the efficiency of bortezomib conjugated to pegylated gold nanoparticles: an in vitro study on human pancreatic cancer cells and adenocarcinoma human lung alveolar basal epithelial cells

ABSTRACT

Objectives: Gold nanoparticles have become promising vectors for cancer diagnosis and treatment. The present study investigates the effect of bortezomib (BTZ), a proteasome inhibitor, conjugated with pegylated gold nanoparticles (PEGAuNPs) in pancreatic and lung cancer cells.

Methods: Synthesized gold nanoparticles (PEGAuNPs) were conjugated with bortezomib antitumor drug. We investigated the cytotoxicity induced by BTZ conjugated with functionalized gold nanoparticles in vitro, in the human pancreatic (S2-013) and lung (A549) cancer cell lines.

Results: We found an efficient of conjugation of BTZ with PEGAuNPs. In vitro assays showed that after 72 h’ incubation with PEGAuNPs-BTZ cancer cells revealed alterations in morphology; also for S2-013 and A549 cancer cells, the IC₅₀ value of free BTZ is respectively 1.5 and 4.3 times higher than the IC₅₀ value of PEGAuNPs-BTZ. Furthermore, for TERT-HPNE, the IC₅₀ value is around 63 times lower for free BTZ than the conjugated nanovehicle. Cell growth inhibition results showed a remarkable enhancement in the effect of BTZ when conjugated with AuNPs.

Conclusions: Our findings showed that conjugation with PEGAuNPs enhance the BTZ growth-inhibition effect on human cancer cells (S2-013 and A549) and decreases its toxicity against normal cells (TERT-HPNE).     

Tumor-targeted/reduction-triggered composite multifunctional nanoparticles for breast cancer chemo-photothermal combinational therapy

Breast cancer has become the most commonly diagnosed cancer type in the world. A combination of chemotherapy and photothermal therapy (PTT) has emerged as a promising strategy for breast cancer therapy. However, the intricacy of precise delivery and the ability to initiate drug release in specific tumor sites remains a challenging puzzle. Therefore, to ensure that the therapeutic agents are synchronously delivered to the tumor site for their synergistic effect, a multifunctional nanoparticle system (PCRHNs) is developed, which is grafted onto the prussian blue nanoparticles (PB NPs) by reduction-responsive camptothecin (CPT) prodrug copolymer, and then modified with tumor-targeting peptide cyclo(Asp-d-Phe-Lys-Arg-Gly) (cRGD) and hyaluronic acid (HA). PCRHNs exhibited nano-sized structure with good monodispersity, high load efficiency of CPT, triggered CPT release in response to reduction environment, and excellent photothermal conversion under laser irradiation. Furthermore, PCRHNs can act as a photoacoustic imaging contrast agent-guided PTT. In vivo studies indicate that PCRHNs exhibited excellent biocompatibility, prolonged blood circulation, enhanced tumor accumulation, allow tumor-specific chemo-photothermal therapy to achieve synergistic antitumor effects with reduced systemic toxicity. Moreover, hyperthermia-induced upregulation of heat shock protein 70 in the tumor cells could be inhibited by CPT. Collectively, PCRHNs may be a promising therapeutic way for breast cancer therapy.     

The role of adjuvant therapy for pancreatic cancer

Patients with pancreatic cancer have a very poor outlook. There have been major advances in the standard surgical treatment of this disease, resulting in decreased post-operative mortality and morbidity. The use of chemotherapy and radiotherapy has been developed to increase long-term patient survival following potentially curative resection. The standard chemotherapeutic agent is 5-fluorouracil (5-FU), although newer cytotoxic agents are in clinical trials for advanced cancer. Initial studies of adjuvant therapy have been based on small numbers of patients, but recently two large European randomised controlled trials of adjuvant therapy (EORTC and ESPAC-1) have been completed. These suggest that adjuvant chemotherapy has a significant survival advantage over resection alone but chemoradiotherapy does not. Promising new agents are being developed and tested mainly in clinical trials of advanced pancreatic cancer. The results of large-scale randomised controlled trials to assess adjuvant therapies for pancreatic cancer demonstrate the great surgical and oncological progress that has been made over the past decade.     

PAR-4 as a possible new target for pancreatic cancer therapy

Importance of the field: Pancreatic cancer (PC) is a deadly disease that is intractable to currently available treatment regimens. Although well described in different tumors types, the importance of apoptosis inducer prostate apoptosis response-4 (Par-4) in PC has not been appreciated. PC is an oncogenic kras driven disease, which is known to downregulate Par-4. Therefore, this review highlights its significance and builds a strong case supporting the role of Par-4 as a possible therapeutic target in PC.

Areas covered in this review: Literature-based evidence spanning the last 15 years on Par-4 and its significance in PC.

What the reader will gain: This review provides comprehensive knowledge of the significance of Par-4 and its association with kras status in PC, along with the crosstalk with crucial resistance and survival molecules NF-κB and Bcl-2 that ultimately are responsible for the overall poor outcome of different therapeutic approaches in this disease.

Take home message: Par-4 holds promise as a potential therapeutic target that can be induced by chemopreventive agents and small-molecule inhibitors either alone or in combination with standard chemotherapeutics leading to selective apoptosis in PC cells. It also acts as a chemosensitizer and therefore warrants further clinical investigations in this disease.     

Emerging pathways and future targets for the molecular therapy of pancreatic cancer

Introduction: Pancreatic cancer treatment remains a challenge for clinicians and researchers. Despite undisputable advances in the comprehension of the molecular mechanisms underlying cancer development and progression, early disease detection and clinical management of patients has made little, if any, progress in the past 20 years. Clinical development of targeted agents directed against validated pathways, such as the EGF/EGF receptor axis, the mutant KRAS protein, MMPs, and VEGF-mediated angiogenesis, alone or in combination with gemcitabine-based standard chemotherapy, has been disappointing.

Areas covered: This review explores the preclinical rationale for clinical approaches aimed at targeting the TGF-β, IGF, Hedgehog, Notch and NF-κB signaling pathways, to develop innovative therapeutic strategies for pancreatic cancer.

Expert opinion: Although some of the already clinically explored approaches (particularly EGFR and KRAS targeting) deserve further clinical consideration, by employing more innovative and creative clinical trial designs than the gemcitabine–targeted agent paradigm that has thus far invariably failed, the targeting of emerging and relatively unexplored signaling pathways holds great promise to increase our understanding of the complex molecular biology and to advance the clinical management of pancreatic cancer.     

Surface plasmon resonance-induced photoactivation of gold nanoparticles as mitochondria-targeted therapeutic agents for pancreatic cancer

Background: Noble metal nanoparticles such as gold nanoparticles can strongly absorb light in the visible region by inducing coherent collective oscillation of conduction band electrons in strong resonance with visible frequencies of light. This phenomenon is frequently termed as surface plasmon resonance (SPR).

Objectives: The main objective was to study the effects of laser photoactivated gold nanoparticles (by means of SPR) on human pancreatic cancer cells.

Results: Gold nanoparticles obtained using standard wet chemical methods (with sodium borohydride as a reducing agent) underwent photoexcitation using 2w 808 nm laser and further administered to 1.4E7 pancreatic cancer cell lines. Flow cytometry, transmission electron microscopy, phase contrast microscopy, quantitative proteomics and confocal microscopy combined with immunochemical staining were used to examine the interaction between photo excited gold nanoparticles and pancreatic cancer cells.

Conclusion: The study shows that phonon–phonon interactions following laser photoexcitation of gold nanoparticles exhibit increased intracellular uptake, as well as mitochondrial swelling, closely followed by mitochondrial inner membrane permeabilization and depolarization. This unique data may represent a major step in mitochondria-targeted anticancer therapies using laser-activated gold nanoparticles.     

Systemic therapy for advanced pancreatic cancer: individualising cytotoxic therapy

Introduction: Pancreatic cancer is an aggressive solid tumour associated with a high risk of local invasion and metastatic spread. In the absence of validated screening approaches, many patients present with advanced, incurable disease. Despite advances in treatment, the prognosis for patients with advanced pancreatic cancer remains poor. The benefits of surgical resection and radiation are unproven in this setting and, as patients generally present with distant metastases, systemic therapy forms the mainstay of treatment. The importance of selecting the optimal cytotoxic therapy remains to be critical to improving outcome and retaining quality of life. This review sets out to compare the current therapies available for advanced pancreatic cancer.

Areas covered: This review examines the evolution of the systemic management of advanced pancreatic cancer, with a particular focus on the landmark Phase III trials identified from an extensive PubMed and Google scholar literature search. The article summarises the cytotoxic agents in use and the results of two decades of clinical trials to culminate in an almost doubling of survival in clinical trials.

Expert opinion: In the concluding expert opinion, the challenges interpreting and translating trial results into clinical practice are discussed, where patients are often older and of worse performance status. In the future, novel biomarkers might be used to tailor therapy.     

A comparison of mesoporous silica nanoparticles and mesoporous organosilica nanoparticles as drug vehicles for cancer therapy

Mesoporous silica nanoparticles (MSNs) are promising drug carriers for use in cancer treatment owing to their excellent biocompatibility and drug‐loading capacity. However, MSN's incomplete drug release and toxic bioaccumulation phenomena limit their clinical application. Recently, researchers have presented redox responsive mesoporous organosilica nanoparticles containing disulfide (S–S) bridges (ss‐MONs). These nanoparticles retained their ability to undergo structural degradation and increased their local release activity when exposed to reducing agents. Disulfide‐based mesoporous organosilica nanoparticles offer researchers a better option for loading chemotherapeutic drugs due to their effective biodegradability through the reduction of glutathione. Although the potential of ss‐MONs in cancer theranostics has been studied, few researchers have systematically compared ss‐MONs with MSNs with regard to endocytosis, drug release, cytotoxicity, and therapeutic effect. In this work, ss‐MONs and MSNs with equal morphology and size were designed and used to payload doxorubicin hydrochloride (DOX) for liver cancer chemotherapy. The ss‐MONs showed considerable degradability in the presence of glutathione and performed comparably to MSNs on biocompatibility measures, including cytotoxicity and endocytosis, as well as in drug‐loading capacity. Notably, DOX‐loaded ss‐MONs exhibited higher intracellular drug release in cancer cells and better anticancer effects in comparison with DOX‐loaded MSNs. Hence, the ss‐MONs may be more desirable carriers for a highly efficient and safe treatment of cancer.     

Animal models of pancreatic cancer for drug research

Background: The operative and conservative results of therapy in pancreatic ductal adenocarcinoma remain appallingly poor. This underlines the demand for further research for effective anticancer drugs. The various animal models remain the essential method for the determination of efficacy of substances during preclinical phase. Objective: Unfortunately, most of these tested substances showed a good efficacy in pancreatic carcinoma in the animal model but were not confirmed during the clinical phase. Methods: The available literature in PubMed, Medline, Ovid and secondary literature was searched regarding the available animal models for drug testing against pancreatic cancer. The models were analyzed regarding their pros and cons in anticancer drug testing. Conclusion: The different modifications of the orthotopic model (especially in mice) seem at present to be the best model for anticancer testing in pancreatic carcinoma. The value of genetically engineered animal model (GEM) and syngeneic models is on debate. A good selection of the model concerning the questions supposed to be clarified may improve the comparability of the results of animal experiments compared to clinical trials.     

In vitro models of pancreatic cancer for translational oncology research

Background: Pancreatic cancer is a disease of near uniform fatality and the overwhelming majority of patients succumb to their advanced malignancy in a few months of diagnosis. Despite considerable advances in our understanding of molecular mechanisms underlying pancreatic carcinogenesis, this knowledge has not yet been fully translated into clinically available treatment strategies that yield significant improvements in disease free or overall survival. Objective: Cell line-based in vitro model systems provide powerful tools to identify potential molecular targets for therapeutic intervention as well as for initial preclinical evaluation of novel drug candidates. Here, we provide a brief overview of recent literature on cell line-based model systems of pancreatic cancer and their application in the search for novel therapeutics against this vicious disease. Conclusion: Although in vitro models of pancreatic cancer are of tremendous value for genetic studies and for initial functional screenings in drug discovery, they carry several immanent drawbacks and are often poor in predicting therapeutic response in humans. Therefore, in most instances, they are successfully exploited to generate hypothesis and identify molecular targets for novel therapeutics, which are subsequently subject to further in-depth characterization using more advanced in vivo model systems and clinical trials.     

Polymeric nanoparticles for cancer therapy

Cancer is an ever-increasing menace that needs to be curbed soon. Though chemotherapy is successful to some extent, the main drawbacks of chemotherapy is the limited accessibility of drugs to the tumor tissues requiring high doses, their intolerable toxicity, development of multiple drug resistance and their non-specific targeting. Nanoparticles (NPs), an evolution of nanotechnology, have the potential to successfully address these problems related to drug delivery and retention and are considered potential candidates to carry drugs to the desired site of therapeutic action. In this review, we give an overview of the use of clinically applicable NPs mainly for cancer therapy. We also focus on the different types of nanoscale polymer carriers used for the delivery of chemotherapeutic agents and the mechanisms that facilitate their targeted delivery to tumor cells.     

白蛋白结合型紫杉醇联合吉西他滨治疗局部进展期胰腺癌的疗效观察

目的评估白蛋白结合型紫杉醇联合吉西他滨治疗局部进展期胰腺癌的有效性及安全性。方法20例经病理确诊不能手术的局部进展期胰腺癌患者,给予白蛋白结合型紫杉醇+吉西他滨方案化疗:白蛋白结合型紫杉醇125 mg/m~2,吉西他滨1 000 mg/m~2,d1、d8给药,21 d重复1次。结果所有患者均进行疗效评价,其中完全缓解(CR)2例,部分缓解(PR)6例,疾病稳定(SD)9例,疾病进展(PD)3例。客观有效率(ORR):40%,疾病控制率(DCR):85%。中位无进展生存期(mPFS)和中位生存期(mOS)分别为5.5个月和10.3个月,1年生存率为40%。所有患者均未发生因不能耐受不良反应而停止治疗及治疗相关性死亡。其中主要的不良反应为:骨髓抑制、脱发、恶心呕吐、乏力、周围神经毒性。结论白蛋白结合型紫杉醇联合吉西他滨治疗局部进展期胰腺癌具有良好的有效性及安全性。     

Emerging antibodies for the treatment of pancreatic cancer

Introduction: Pancreatic ductal adenocarcinoma cancer (PDAC) is the fourth leading cause of cancer death worldwide. Recently, two chemotherapy regimens have proven to improve median overall survival in comparison with gemcitabine. Based on better understanding of tumor molecular biology and of the role of tumor microenvironment, monoclonal antibodies (mAbs) could be an interesting and new type of targeted treatment of PDAC.

Areas covered: Preclinical and clinical trials have evaluated the efficacy of several mAbs in pancreatic cancer treatment. This review will underline the most important targeted pathways by mAbs involved in this disease, including EGFR, HER-2, IGF-1 R, VEGF/VEGFR, NOTCH, WNT and immune checkpoints.

Expert opinion: Despite the promising results of preclinical and phase I trials, the addition of mAbs to standard chemotherapy or in association with other target agents seems not to confirm these results in the following phase II and III trials in pancreatic cancer patients. However, an improved patient selection before treatment based on molecular characteristics in association with reliable predictive biomarkers can identified more efficacious treatment approaches, minimizing toxicity profile of these drugs.     

Fabrication of gold nanoparticles for targeted therapy in pancreatic cancer

The targeted delivery of a drug should result in enhanced therapeutic efficacy with low to minimal side effects. This is a widely accepted concept, but limited in application due to lack of available technologies and process of validation. Biomedical nanotechnology can play an important role in this respect. Biomedical nanotechnology is a burgeoning field with myriads of opportunities and possibilities for advancing medical science and disease treatment. Cancer nanotechnology (1–100 nm size range) is expected to change the very foundations of cancer treatment, diagnosis and detection. Nanomaterials, especially gold nanoparticles (AuNPs) have unique physico-chemical properties, such as ultra small size, large surface area to mass ratio, and high surface reactivity, presence of surface plasmon resonance (SPR) bands, biocompatibility and ease of surface functionalization. In this review, we will discuss how the unique physico-chemical properties of gold nanoparticles may be utilized for targeted drug delivery in pancreatic cancer leading to increased efficacy of traditional chemotherapeutics.     

胰腺癌的流行病学与诊治现状分析

胰腺癌恶性程度高,手术切除率低,预后极差,其早期症状表现不典型,所以早期诊断较难。我国胰腺癌的发病率呈逐年上升趋势,但目前国内在胰腺癌的诊治中尚存在许多不足,胰腺癌相关的基础研究不够深入。本文对胰腺癌的最新流行病学数据、诊治现状及存在的问题进行了分析,为当下国内胰腺癌的诊疗提供参考。     

cRGD peptide-conjugated polyethylenimine-based lipid nanoparticle for intracellular delivery of siRNA in hepatocarcinoma therapy

The effective delivery system plays an important role in the application of siRNA in the antitumor study. However, until now, researches on the delivery systems targeting hepatocarcinoma cells are still being explored. Here we designed and prepared a novel siRNA delivery system, cRGD-PSH-NP, which was based on a modified polyethyleneimine (PSH) and DSPE-PEG₂₀₀₀-cRGD. cRGD-PSH-NP loaded with survivin siRNA (cRGD-PSH-NP/S) was composed of egg phosphatidylcholine, cationic PSH, PEGylated lipids, survivin siRNA, and cRGD peptide as a targeting ligand. The formulations of cRGD-PSH-NP/S were optimized and characterized. In vitro investigations showed excellent gene silencing and antitumor activity compared with the unmodified nanoparticles in HepG2 cells. In vivo antitumor efficacy of cRGD-PSH-NP/S exhibited potent tumor inhibition (74.71%) in HepG2-bearing nude mice without inducing toxicity. These data suggested further research of cRGD-PSH-NP/S in hepatocarcinoma therapy.     

Pharmacotherapeutic strategies for treating pancreatic cancer: advances and challenges

Introduction: Despite many efforts to improve the outcome of pancreatic ductal adenocarcinoma (PDAC), its prognosis remains poor, which is mostly related to late diagnosis and drug resistance. Improving systemic therapy is considered the major challenge in improving the outcome of this disease.

Areas covered: This review covers novel chemotherapy and targeted agents in the treatment of PDAC, with a focus on advanced stage disease.

Expert opinion: Current frontline therapies used in the treatment of patients with PDAC with favorable performance status are gemcitabine (GEM) and nab-paclitaxel or 5-fluorouracil, leucovorin, irinotecan, and oxaliplatin (FOLFIRINOX). PDAC has a number of genetic mutations that may explain its biological behavior, such as KRAS, p53 and CDK2NA, which occur in more than 90% of cases. Unfortunately, to this day, a specific targeting agent to any of those frequent gene mutations is lacking. Emerging areas of targeted therapies include the DNA repair, stroma, metabolism, and stem cells. Immunotherapy with either vaccines or immune checkpoint inhibitors has not produced any significant improvements in outcome of PDAC. Incorporating different approaches in therapy, including conventional, immunological, and others, is key in offering patients with the best possible care.     

环氧合酶-2及其抑制剂在胰腺癌血管靶向治疗中的作用

胰腺癌的诊治目前仍是医学界的难题,血管生成是胰腺癌生长和转移的必要因素。环氧合酶(cyclooxygenase,COX)为花生四烯酸代谢过程中的关键酶,存在COX-1及COX-2两种同工酶,其中COX-2在胰腺癌的发生发展及胰腺癌血管生成中发挥重要作用。COX-2抑制剂可分为非选择性及选择性两种,两种COX-2抑制剂都对胰腺癌及其血管形成的发生与进展存在抑制作用,COX-2抑制剂抗肿瘤血管形成的机制可能是抑制血管内皮生长因子(VEGF)、缺氧诱导因子-1及基质金属蛋白酶(MMP)的表达、降低前列腺素(PGs)及其他血管生成因子的表达、促进内皮细胞凋亡、抑制内皮细胞侵袭力和影响一氧化氮合酶(NOS)的表达。     

Celastrol-conjugated chitosan oligosaccharide for the treatment of pancreatic cancer

Celastrol is a promising antitumor drug candidate, but the poor water solubility and cytotoxicity limit its clinical application. Herein, we synthesized a Celastrol (Cel)-chitosan oligosaccharide (CSO) conjugate (Cel-CSO) for drug delivery. Celastrol was conjugated to a CSO backbone via amide bond formation, which was verified by infrared spectrum (IR) analyses. The Cel-CSO contained ∼10 wt% of Celastrol showed excellent aqueous solubility (18.6 mg/mL) in comparation with the parent Celastrol. Cel-CSO significantly inhibited tumor growth, induced apoptosis, and effectively suppressed tumor metastasis in human pancreatic cancer cells (BxPC-3). While the cytotoxicity of Cel-CSO in hepatic cells (HL7702) was lower than that of the free Celastrol. Cel-CSO enhanced the anticancer efficacy, promoted the circulation time of Celastrol, and reduced the subacute toxicity, which indicated that CSO can be a promising Celastrol delivery system for pancreatic cancer therapy.