Pancreatic Cancer: Recent Advances in Nanoformulation-Based Therapies

PAFAH1B3 is a KLF9 target gene that promotes proliferation and metastasis in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal human malignancies. Uncontrolled cell proliferation, invasion and migration of pancreatic cancer cells are the fundamental causes of death in PDAC patients. Our previous studies showed that KLF9 inhibits the proliferation, invasion and migration of pancreatic cancer cells. However, the underlying mechanisms are not fully understood. In this study, we found that platelet-activating factor acetylhydrolase IB3 (PAFAH1B3) is highly expressed in pancreatic cancer tissues and cells. In vitro and in vivo studies showed that overexpression of PAFAH1B3 promoted the proliferation and invasion of pancreatic cancer cells, while downregulation of PAFAH1B3 inhibited these processes. We found that KLF9 expression is negatively correlated with PAFAH1B3 expression in pancreatic cancer tissues and cells. Western blotting revealed that KLF9 negatively regulates the expression of PAFAH1B3 in pancreatic cancer tissues and cells. Rescue experiments showed that overexpression of PAFAH1B3 could partially attenuate the suppression of pancreatic cancer cell proliferation, invasion and migration induced by KLF9 overexpression. Finally, chromatin immunoprecipitation (ChIP) and dual-luciferase reporter assays were carried out, and the results showed that KLF9 directly binds to the promoter of PAFAH1B3 and inhibits its transcriptional activity. In conclusion, our study indicated that KLF9 can inhibit the proliferation, invasion, migration and metastasis of pancreatic cancer cells by inhibiting PAFAH1B3.

Membrane-enclosed Pseudomonas quinolone signal attenuates bacterial virulence by interfering with quorum sensing

Outer membrane vesicle (OMV)-delivered Pseudomonas quinolone signal (PQS) plays a critical role in cell-cell communication in Pseudomonas aeruginosa. However, the functions and mechanisms of membrane-enclosed PQS in interspecies communication in microbial communities are not clear. Here, we demonstrate that PQS delivered by both OMVs from P. aeruginosa and liposome reduces the competitiveness of Burkholderia cenocepacia, which usually shares the same niche in the lungs of cystic fibrosis patients, by interfering with quorum sensing (QS) in B. cenocepacia through the LysR-type regulator ShvR. Intriguingly, we found that ShvR regulates the production of the QS signals cis-2-dodecenoic acid (BDSF) and N-acyl homoserine lactone (AHL) by directly binding to the promoters of signal synthase-encoding genes. Perception of PQS influences the regulatory activity of ShvR and thus ultimately reduces QS signal production and virulence in B. cenocepacia. Our findings provide insights into the interspecies communication mediated by the membrane-enclosed QS signal among bacterial species residing in the same microbial community.IMPORTANCEQuorum sensing (QS) is a ubiquitous cell-to-cell communication mechanism. Previous studies showed that Burkholderia cenocepacia mainly employs cis-2-dodecenoic acid (BDSF) and N-acyl homoserine lactone (AHL) QS systems to regulate biological functions and virulence. Here, we demonstrate that Pseudomonas quinolone signal (PQS) delivered by outer membrane vesicles from Pseudomonas aeruginosa or liposome attenuates B. cenocepacia virulence by targeting the LysR-type regulator ShvR, which regulates the production of the QS signals BDSF and AHL in B. cenocepacia. Our results not only suggest the important roles of membrane-enclosed PQS in interspecies and interkingdom communications but also provide a new perspective on the use of functional nanocarriers loaded with QS inhibitors for treating pathogen infections.

Cancer Metabolism as a Therapeutic Target and Review of Interventions

Cancer is amenable to low-cost treatments, given that it has a significant metabolic component, which can be affected through diet and lifestyle change at minimal cost. The Warburg hypothesis states that cancer cells have an altered cell metabolism towards anaerobic glycolysis. Given this metabolic reprogramming in cancer cells, it is possible to target cancers metabolically by depriving them of glucose. In addition to dietary and lifestyle modifications which work on tumors metabolically, there are a panoply of nutritional supplements and repurposed drugs associated with cancer prevention and better treatment outcomes. These interventions and their evidentiary basis are covered in the latter half of this review to guide future cancer treatment.

Therapeutic potential of curcumin and its nanoformulations for treating oral cancer

The global incidence of oral cancer has steadily increased in recent years and is associated with high morbidity and mortality. Oral cancer is the most common cancer in the head and neck region, and is predominantly of epithelial origin (i.e. squamous cell carcinoma). Oral cancer treatment modalities mainly include surgery with or without radiotherapy and chemotherapy. Though proven effective, chemotherapy has significant adverse effects with possibilities of tumor resistance to anticancer drugs and recurrence. Thus, there is an imperative need to identify suitable anticancer therapies that are highly precise with minimal side effects and to make oral cancer treatment effective and safer. Among the available adjuvant therapies is curcumin, a plant polyphenol isolated from the rhizome of the turmeric plant Curcuma longa. Curcumin has been demonstrated to have anti-infectious, antioxidant, anti-inflammatory, and anticarcinogenic properties. Curcumin has poor bioavailability, which has been overcome by its various analogues and nanoformulations, such as nanoparticles, liposome complexes, micelles, and phospholipid complexes. Studies have shown that the anticancer effects of curcumin are mediated by its action on multiple molecular targets, including activator protein 1, protein kinase B (Akt), nuclear factor κ-light-chain-enhancer of activated B cells, mitogen-activated protein kinase, epidermal growth factor receptor (EGFR) expression, and EGFR downstream signaling pathways. These targets play important roles in oral cancer pathogenesis, thereby making curcumin a promising adjuvant treatment modality. This review aims to summarize the different novel formulations of curcumin and their role in the treatment of oral cancer.

Nanocarriers targeting the diseases of the pancreas

Diseases of the pancreas include acute and chronic pancreatitis, exocrine pancreatic insufficiency, diabetes and pancreatic cancer. These pathologies can be difficult to treat due to the innate properties of the pancreas, its structure and localization. The need for effective targeting of the pancreatic tissue by means of nanoparticles delivering therapeutics is a major focus area covered and discussed in this review. Most common diseases of the pancreas do not have specific and direct medical treatment option, and existing treatment options are generally aimed at relieving symptoms. Diabetes has different treatment options for different subtypes based on insulin having stability problems and requiring injections reducing patient compliance. Pancreatic cancer progresses silently and can only be diagnosed in advanced stages. Therefore, survival rate of patients is very low. Gemcitabine and FOLFIRINOX treatment regimens, the most commonly used clinical standard treatments, are generally insufficient due to the chemoresistance that develops in cancer cells and also various side effects. Therefore new treatment options for pancreatic cancer are also under focus. Overcoming drug resistance and pancreatic targeting can be achieved with active and passive targeting methods, and a more effective and safer treatment regimen can be provided at lower drug doses. This review covers the current literature and clinical trials concerning pancreatic drug delivery systems in the nanoscale focusing on the challenges and opportunities provided by these smart delivery systems.

Cancer Chemoprevention Using Nanotechnology-Based Approaches

Cancer research in pursuit of better diagnostic and treatment modalities has seen great advances in recent years. However, the incidence rate of cancer is still very high. Almost 40% of women and men are diagnosed with cancer during their lifetime. Such high incidence has not only resulted in high mortality but also severely compromised patient lifestyles, and added a great socioeconomic burden. In view of this, chemoprevention has gained wide attention as a method to reduce cancer incidence and its relapse after treatment. Among various stems of chemoprevention research, nanotechnology-based chemoprevention approaches have established their potential to offer better efficacy and safety. This review summarizes recent advances in nanotechnology-based chemoprevention strategies for various cancers with emphasis on lung and bronchial cancer, colorectal, pancreatic, and breast cancer and highlights the unmet needs in this developing field towards successful clinical translation.

Novel fucoidan based bioactive targeted nanoparticles from Undaria Pinnatifida for treatment of pancreatic cancer

Fucoidan is a marine polymer extracted from diverse types of brown algae. This polysaccharide showed great potential towards treatment of different types of cancer. In this study, the activity of fucoidan extracted from Undaria Pinnatifida was investigated against pancreatic cancer (one of the most life-threatening cancers). Then, in an attempt to enhance the polymer's activity against cancer cells, conversion the polymer solution to nanoparticles was suggested to enhance its delivery through pancreatic cancer surrounding stroma. Novel fucoidan based nanoparticles were elaborated by polyelectrolyte interaction with the positively charged, active targeting ligand lactoferrin. The formulation was optimized through the interplay between different factors. Effect of fucoidan solution along with its blank nanoparticles was tested on the viability of pancreatic cancer cells and its migration and invasion abilities. Results confirmed the cytotoxic ability of fucoidan against pancreatic cancer. IC50 value decreased by 2.3 folds when the polymer was converted to nanoparticles. The prepared nanosystems showed an enhanced ability to prevent pancreatic cancer cells' migration and invasion. Results suggested the potential of using these nanoparticles as bioactive dual-targeted system either blank or loaded with different anticancer agents for treatment for pancreatic cancer.

Curcumin Combination Chemotherapy: The Implication and Efficacy in Cancer

Many chemotherapeutic drugs have been used for the treatment of cancer, for instance, doxorubicin, irinotecan, 5-fluorouracil, cisplatin, and paclitaxel. However, the effectiveness of chemotherapy is limited in cancer therapy due to drug resistance, therapeutic selectivity, and undesirable side effects. The combination of therapies with natural compounds is likely to increase the effectiveness of drug treatment as well as reduce the adverse outcomes. Curcumin, a polyphenolic isolated from Curcuma longa, belongs to the rhizome of Zingiberaceae plants. Studies from in vitro and in vivo revealed that curcumin exerts many pharmacological activities with less toxic effects. The biological mechanisms underlying the anticancer activity of co-treatment curcumin and chemotherapy are complex and worth to discuss further. Therefore, this review aimed to address the molecular mechanisms of combined curcumin and chemotherapy in the treatment of cancer. The anticancer activity of combined nanoformulation of curcumin and chemotherapy was also discussed in this study. Taken together, a better understanding of the implication and underlying mechanisms of action of combined curcumin and chemotherapy may provide a useful approach to combat cancer diseases.

Loratadine self-microemulsifying drug delivery systems (SMEDDS) in combination with sulforaphane for the synergistic chemoprevention of pancreatic cancer

Pancreatic cancer (PC), currently the third leading cause of cancer-related deaths in the USA, is projected to become the second leading cause, behind lung cancer, by 2020. The increasing incidence, low survival rate, and limited treatment opportunities necessitate the use of alternative approaches such as chemoprevention, to tackle PC. In this study, we report significant synergistic chemoprevention efficacy for the first time from a low-dose combination of a classical antihistaminic drug, Loratadine (LOR) and a neutraceutical compound, Sulforaphane (SFN) using a self-microemulsifying drug delivery system (SMEDDS) formulation. The formulation was developed using Quality by Design approach (globule size, 95.13 ± 7.9 nm; PDI, 0.17 ± 0.04) and revealed significant (p < 0.05) enhancement in the in vitro dissolution profile confirming the enhanced solubility of BCS class II drug LOR with SMEDDS formulation. The LOR-SFN combination revealed ~ 40-fold reduction in IC50 concentration compared to LOR alone in MIA PaCa-2 and Panc-1 cell lines respectively, confirming the synergistic enhancement in chemoprevention. Further, the nanoformulation resulted in ~ 7-fold and ~ 11-fold reduction in IC50 values compared to LOR-SFN combination. Hence, our studies successfully demonstrate that a unique low-dose combination of LOR encapsulated within SMEDDs with SFN shows significantly enhanced chemopreventive efficacy of PC.