Comparative immune profiling of pancreatic ductal adenocarcinoma progression among South African patients.

BACKGROUND: Pancreatic Ductal Adenocarcinoma (PDAC) is an aggressive cancer characterized by an immunosuppressive microenvironment. Patients from specific ethnicities and population groups have poorer prognoses than others. Therefore, a better understanding of the immune landscape in such groups is necessary for disease elucidation, predicting patient outcomes and therapeutic targeting. This study investigated the expression of circulating key immune cell markers in South African PDAC patients of African ancestry. METHODS: Blood samples were obtained from a total of 6 healthy volunteers (HC), 6 Chronic Pancreatitis (CP) and 34 PDAC patients consisting of 22 resectable (RPC), 8 locally advanced (LAPC) and 4 metastatic (MPC). Real-time Quantitative Polymerase Chain reactions (RT-qPCR), Metabolomics, Enzyme-Linked Immunosorbent Assay (ELISA), Reactive Oxygen Species (ROS), and Immunophenotyping assays were conducted. Statistical analysis was conducted in R (v 4.3.2). Additional analysis of single-cell RNA data from 20 patients (16 PDAC and 4 controls) was conducted to interrogate the distribution of T-cell and Natural Killer cell populations. RESULTS: Granulocyte and neutrophil levels were significantly elevated while lymphocytes decreased with PDAC severity. The total percentages of CD3 T-cell subpopulations (helper and double negative T-cells) decreased when compared to HC. Although both NK (p = 0.014) and NKT (p < 0.001) cell levels increased as the disease progressed, their subsets: NK CD56dimCD16- (p = 0.024) and NKTs CD56+ (p = 0.008) cell levels reduced significantly. Of note is the negative association of NK CD56dimCD16- (p < 0.001) cell levels with survival time. The gene expression analyses showed no statistically significant correlation when comparing the PDAC groups with the controls. The inflammatory status of PDAC was assessed by ROS levels of serum which were elevated in CP (p = 0.025), (RPC (p = 0.003) and LAPC (p = 0.008)) while no significant change was observed in MPC, compared to the HC group. ROS was shown to be positively correlated with GlycA (R = 0.45, p = 0.0096). Single-cell analyses showed a significant difference in the ratio of NKT cells per total cell counts in LAPC (p < 0.001) and MPC (p < 0.001) groups compared with HC, confirming observations in our sample group. CONCLUSION: The expression of these immune cell markers observed in this pilot study provides insight into their potential roles in tumour progression in the patient group and suggests their potential utility in the development of immunotherapeutic strategies.

Treatment Strategies for Multiple Myeloma Treatment and the Role of High-Throughput Screening for Precision Cancer Therapy.

In the past few years, development of approved drug candidates has improved the disease management of multiple myeloma (MM). However, due to drug resistance, some of the patients do not respond positively, while some of the patients acquire drug resistance, thereby these patients eventually relapse. Hence, there are no other therapeutic options for multiple myeloma patients. Therefore, this necessitates a precision-based approach to multiple myeloma therapy. The use of patient's samples to test drug sensitivity to increase efficacy and reduce treatment-related toxicities is the goal of functional precision medicine. Platforms such as high-throughput-based drug repurposing technology can be used to select effective single drug and drug combinations based on the efficacy and toxicity studies within a time frame of couple of weeks. In this article, we describe the clinical and cytogenetic features of MM. We highlight the various treatment strategies and elaborate on the role of high-throughput screening platforms in a precision-based approach towards clinical treatment.

Accuracy of CT Scan for Detecting Hollow Viscus Injury in Penetrating Abdominal Trauma.

BACKGROUND: In penetrating abdominal trauma, computed tomography (CT) is routinely performed to evaluate stable patients for selective non-operative management (SNOM). Triple-contrast CT (oral, rectal, and IV) has traditionally been used. However, due to its disadvantages, most trauma centres, including our unit at the Charlotte Maxeke Johannesburg Academic Hospital (CMJAH), now perform single-contrast intravenous-only CT scans. We performed a retrospective review to determine the accuracy of single-contrast CT scans for detecting hollow viscus injuries (HVI) in penetrating abdominal trauma. METHODS: A retrospective review of all patients who presented to CMJAH with penetrating abdominal injuries was performed between 01 August 2017 and 31 August 2019 and were evaluated for SNOM with CT (IV contrast only). Patient records were reviewed to determine pertinent demographics, mechanism, and site of injury, as well as metabolic parameters. CT findings were compared to findings at laparotomy. RESULTS: A total of 437 patients met the inclusion criteria. The majority were male (92.7%), with a mean age of 31.5 yrs (SD 8.7). Injuries were predominantly due to stab wounds (72,5%, n = 317). CT scan was negative in 342 patients, of which 314 completed SNOM successfully. A total of 93 patients proceeded to laparotomy. CT had a sensitivity of 95.1%, specificity of 44.2%, positive predictive value of 57.4%, and negative predictive value of 92%. CONCLUSION: Single-contrast CT in penetrating abdominal trauma is a valuable investigative tool in identifying patients for SNOM. Features of HVI on single-contrast CT are not very specific and should be interpreted along with other clinical factors including wound trajectory and serial abdominal examinations. Other associated injuries such as diaphragmatic and solid organ injuries should be considered in the final management plan.

Polyethyleneglycol-Betulinic Acid (PEG-BA) Polymer-Drug Conjugate Induces Apoptosis and Antioxidation in a Biological Model of Pancreatic Cancer.

Pancreatic cancer (PC) is one of the most aggressive solid malignancies with poor treatment response and low survival rates. Herbal medicines such as betulinic acid (BA) have shown potential in treating various solid tumours, but with limitations that can be circumvented by polymer-drug conjugation. Polyethylene glycol-BA (PEG-BA) polymer-drug conjugate has previously shown selective anticancer activity against PC cells. Here, we elucidate the mechanism of cell death and the cell death pathway, anti-inflammatory and antioxidant activities of PEG-BA. PEG-BA induced apoptotic cell death by arresting MIA-PaCa-2 cells in the Sub-G1 phase of the cell cycle compared with BA and untreated cells (39.50 ± 5.32% > 19.63 ± 4.49% > 4.57 ± 0.82%). NFκB/p65 protein expression was moderately increased by PEG-BA (2.70 vs. 3.09 ± 0.42 ng/mL; p = 0.1521). However, significant (p < 0.05) overexpression of the proapoptotic genes TNF (23.72 ± 1.03) and CASPASE 3 (12,059.98 ± 1.74) compared with untreated cells was notable. The antioxidant potential of PEG-BA was greater (IC50 = 15.59 ± 0.64 µM) compared with ascorbic acid (25.58 ± 0.44 µM) and BA-only (>100 µM) and further confirmed with the improved reduction of hydroperoxide levels compared with BA-only (518.80 ± 25.53 µM vs. 542.43 ± 9.70 µM). In conclusion, PEG-BA activated both the intrinsic and extrinsic pathways of apoptosis and improved antioxidant activities in PC cells, suggesting enhanced anticancer activity upon conjugation.

Application of Drug Repurposing-Based Precision Medicine Platform for Leukaemia Patient Treatment.

Drug resistance in leukaemia is a major problem that needs to be addressed. Precision medicine provides an avenue to reduce drug resistance through a personalised treatment plan. It has helped to better stratify patients based on their molecular profile and therefore improved the sensitivity of patients to a given therapeutic regimen. However, therapeutic options are still limited for patients who have already been subjected to many lines of chemotherapy. The process of designing and developing new drugs requires significant resources, including money and time. Drug repurposing has been explored as an alternative to identify effective drug(s) that could be used to target leukaemia and lessen the burden of drug resistance. The drug repurposing process usually includes preclinical studies with drug screening and clinical trials before approval. Although most of the repurposed drugs that have been identified are generally safe for leukaemia treatment, they seem not to be good candidates for monotherapy but could have value in combination with other drugs, especially for patients who have exhausted therapeutic options. In this review, we highlight precision medicine in leukaemia and the role of drug repurposing. Specifically, we discuss the several screening methods via chemoinformatic, in vitro, and ex vivo that have facilitated and accelerated the drug repurposing process.

Differential Expression of Platelet Activation Markers, CD62P and CD63, after Exposure to Breast Cancer Cells Treated with Kigelia Africana, Ximenia Caffra and Mimusops Zeyheri Seed Oils In Vitro.

Cancer patients, including breast cancer patients, live in a hypercoagulable state. Chemo- and hormone- therapy used in the treatment of breast cancer increases the risk of thrombosis. Due to differences in health care services between developed and developing countries, the survival rate of women with breast cancer in developing countries is low. Consequently, ethnomedicines are used and their efficacy as potential alternatives are being scientifically explored. The seed oils of Kigelia africana, Ximenia caffra and Mimusops zeyheri have anti-proliferative effects on hormone-dependent (MCF-7) and cytotoxic effects on hormone-independent (MDA-MB-231) breast cancer cells. In this study, we determined if these seed oils reduce the thrombogenic ability of breast cancer cells by measuring the platelet surface expression of the activation-specific antigens CD62P and CD63. MDA-MB-231 and MCF-7 cells were pretreated with the seed oils before being exposed to whole blood of human female volunteers. An increase in CD62P and CD63 expression following whole blood exposure to untreated breast cancer cells was observed. Treated MDA-MB-231 cells reduced CD62P and CD63 expression while treated MCF-7 cells increased CD62P and decreased CD63 expression. Kigelia africana, Ximenia caffra and Mimusops zeyheri seed oils are able to reduce the thrombogenic ability of MDA-MB-231 breast cancer cells.

Prospects of Delivering Natural Compounds by Polymer-Drug Conjugates in Cancer Therapeutics.

Synthetic chemotherapeutics have played a crucial role in minimizing mostly palliative symptoms associated with cancer; however, they have also created other problems such as system toxicity due to a lack of specificity. This has led to the development of polymer-drug conjugates amongst other novel drug delivery systems. Most of the formulations designed using delivery systems consist of synthetic drugs and face issues such as drug resistance, which has already rendered drugs such as antibiotics ineffective. This is further exacerbated by toxicity due to the long-term use. Given these problems and the fact that conjugation of synthetic compounds to polymers has been relatively slow with no formulation on the market after a decade of extensive studies, the focus has shifted to using this platform with medicinal plant extracts to improve solubility, specificity and increase drug release of medicinal and herbal bioactives. In recent years, various plant extracts such as flavonoids, tannins and terpenoids have been studied extensively using this approach. The success of formulations developed using novel drug-delivery systems is highly dependent on the tumour microenvironment especially on the enhanced permeability and retention effect. As a result, the compromised lymphatic network and 'leaky' vasculature exhibited by tumour cells act as a guiding principle in the delivery of these formulations. This review focuses on the state of the polymer-drug conjugates and their exploration with natural compounds, the progress and difficulties thus far, and future directions concerning cancer treatment.

Synthesis of fluorescence labelled aptamers for use as low-cost reagents in HIV/AIDS research and diagnostics.

Aptamers are nucleic acids selected by systematic evolution of ligands by exponential enrichment. They have potential as alternatives to antibodies in medical research and diagnostics, with the advantages of being non-immunogenic and relatively inexpensive to produce. In the present study, gp120 aptamers conjugated with fluorescein isothiocyanate (FITC) were generated, which could interact with HIV-1 gp120. A previously isolated gp120 aptamer, CSIR 1.1, was conjugated with FITC by incubation with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and imidazole. The conjugation and binding to the glycoprotein were confirmed by flow cytometry. FITC conjugated aptamers showed an increase in fluorescence emission 24-fold higher than baseline, and this difference was statistically significant (P=0.0016). Compared with a commercially available biotinylated anti-gp120 antibody, detected using FITC conjugated streptavidin, the emission of fluorescence obtained from the FITC-conjugated aptamer was 8-fold higher, suggesting a stronger interaction with gp120. In addition, the FITC conjugated aptamer neutralized HIV-1 pseudoviruses with an average IC50 of 21.3 nM, similar to the parent aptamer that had an IC50 of 19.2 nM. However, the difference in inhibition between the two aptamers was not statistically significant (P=0.784). These results indicate that the FITC-conjugated aptamer generated in the present study could potentially be used as a low-cost reagent in HIV/AIDS research and diagnostics.

Chemokine receptor 8 expression may be linked to disease severity and elevated interleukin 6 secretion in acute pancreatitis.

BACKGROUND: Acute pancreatitis (AP) is an inflammatory disease, which presents with epigastric pain and is clinically diagnosed by amylase and lipase three times the upper limit of normal. The 2012 Atlanta classification stratifies the severity of AP as one of three risk categories namely, mild AP (MAP), moderately severe AP (MSAP), and severe AP (SAP). Challenges in stratifying AP upon diagnosis suggest that a better understanding of the underlying complex pathophysiology may be beneficial. AIM: To identify the role of the chemokine receptor 8 (CCR8), expressed by T-helper type-2 Lymphocytes and peritoneal macrophages, and its possible association to Interleukin (IL)-6 and AP stratification. METHODS: This study was a prospective case-control study. A total of 40 patients were recruited from the Chris Hani Baragwanath Academic Hospital and the Charlotte Maxeke Johannesburg Academic Hospital. Bioassays were performed on 29 patients (14 MAP, 11 MSAP, and 4 SAP) and 6 healthy controls as part of a preliminary study. A total of 12 mL of blood samples were collected at Day (D) 1, 3, 5, and 7 post epigastric pain. Using multiplex immunoassay panels, real-time polymerase chain reaction (qRT-PCR) arrays, and multicolour flow cytometry analysis, immune response-related proteins, genes, and cells were profiled respectively. GraphPad Prism™ software and fold change (FC) analysis was used to determine differences between the groups. P<0.05 was considered significant. RESULTS: The concentration of IL-6 was significantly different at D3 post epigastric pain in both the MAP group and MSAP group with P = 0.001 and P = 0.013 respectively, in a multiplex assay. When a FC of 2 was applied to identify differentially expressed genes using RT2 Profiler, CCR8 was shown to increase steadily with disease severity from MAP (1.33), MSAP (38.28) to SAP (1172.45) median FC. Further verification studies using RT-PCR showed fold change increases of CCR8 in MSAP and SAP ranging from 1000 to 1000000 times when represented as Log10, compared to healthy control respectively at D3. The findings also showed differing lymphocyte and monocyte cell frequency between the groups. With monocyte population frequency as high as 70% in MSAP at D3. CONCLUSION: The higher levels of CCR8 and IL-6 in the severe patients and immune cell differences compared to MAP and controls provide an avenue for exploring AP stratification to improve management.

Serum Metabolomic and Lipoprotein Profiling of Pancreatic Ductal Adenocarcinoma Patients of African Ancestry.

Pancreatic ductal adenocarcinoma (PDAC) is a lethal cancer with a characteristic dysregulated metabolism. Abnormal clinicopathological features linked to defective metabolic and inflammatory response pathways can induce PDAC development and progression. In this study, we investigated the metabolites and lipoproteins profiles of PDAC patients of African ancestry. Nuclear Magnetic Resonance (NMR) spectroscopy was conducted on serum obtained from consenting individuals (34 PDAC, 6 Chronic Pancreatitis, and 6 healthy participants). Seventy-five signals were quantified from each NMR spectrum. The Liposcale test was used for lipoprotein characterization. Spearman's correlation and Kapan Meier tests were conducted for correlation and survival analyses, respectively. In our patient cohort, the results demonstrated that levels of metabolites involved in the glycolytic pathway increased with the tumour stage. Raised ethanol and 3-hydroxybutyrate were independently correlated with a shorter patient survival time, irrespective of tumour stage. Furthermore, increased levels of bilirubin resulted in an abnormal lipoprotein profile in PDAC patients. Additionally, we observed that the levels of a panel of metabolites (such as glucose and lactate) and lipoproteins correlated with those of inflammatory markers. Taken together, the metabolic phenotype can help distinguish PDAC severity and be used to predict patient survival and inform treatment intervention.

Anti-Cancer and Immunomodulatory Activity of a Polyethylene Glycol-Betulinic Acid Conjugate on Pancreatic Cancer Cells.

Drug delivery systems involving polymer therapeutics enhance drug potency by improved solubility and specificity and may assist in circumventing chemoresistance in pancreatic cancer (PC). We compared the effectiveness of the naturally occurring drug, betulinic acid (BA), alone and in a polymer conjugate construct of polyethylene glycol (PEG), (PEG-BA), on PC cells (MIA PaCa-2), a normal cell line (Vero) and on peripheral blood mononuclear cells (PBMCs). PEG-BA, was tested for its effect on cell death, immunomodulation and chemoresistance-linked signalling pathways. The conjugate was significantly more toxic to PC cells (p < 0.001, IC50 of 1.35 ± 0.11 µM) compared to BA (IC50 of 12.70 ± 0.34 µM), with a selectivity index (SI) of 7.28 compared to 1.4 in Vero cells. Cytotoxicity was confirmed by increased apoptotic cell death. PEG-BA inhibited the production of IL-6 by 4-5.5 fold compared to BA-treated cells. Furthermore, PEG-BA treatment of MIA PaCa-2 cells resulted in the dysregulation of crucial chemoresistance genes such as WNT3A, TXNRD1, SLC2A1 and GATA3. The dysregulation of chemoresistance-associated genes and the inhibition of cytokines such as IL-6 by the model polymer construct, PEG-BA, holds promise for further exploration in PC treatment.

Role of different immune cells and metabolic pathways in modulating the immune response in pancreatic cancer (Review).

Pancreatic cancer is an aggressive cancer, making it a leading cause of cancer­related deaths. It is characteristically resistant to treatment, which results in low survival rates. In pancreatic cancer, immune cells undergo transitions that can inhibit or promote their functions, enabling treatment resistance and tumor progression. These transitions can be fostered by metabolic pathways that are dysregulated during tumorigenesis. The present review aimed to summarize the different immune cells and their roles in pancreatic cancer. The review also highlighted the individual metabolic pathways in pancreatic cancer and how they enable transitions in immune cells. Finally, the potential of targeting metabolic pathways for effective therapeutic strategies was considered.

Areca catechu-From farm to food and biomedical applications.

The family Arecaceae includes 181 genera and 2,600 species with a high diversity in physical characteristics. Areca plants, commonly palms, which are able to grow in nearly every type of habitat, prefer tropical and subtropical climates. The most studied species Areca catechu L. contains phytochemicals as phenolics and alkaloids with biological properties. The phenolics are mainly distributed in roots followed by fresh unripe fruits, leaves, spikes, and veins, while the contents of alkaloids are in the order of roots, fresh unripe fruits, spikes, leaves, and veins. This species has been reputed to provide health effects on the cardiovascular, respiratory, nervous, metabolic, gastrointestinal, and reproductive systems. However, in many developing countries, quid from this species has been associated with side effects, which include the destruction of the teeth, impairment of oral hygiene, bronchial asthma, or oral cancer. Despite these side effects, which are also mentioned in this work, the present review collects the main results of biological properties of the phytochemicals in A. catechu. This study emphasizes the in vitro and in vivo antioxidant, antimicrobial, anticancer, and clinical effectiveness in humans. In this sense, A. catechu have demonstrated effectiveness in several reports through in vitro and in vivo experiments on disorders such as antimicrobial, antioxidant, or anticancer. Moreover, our findings demonstrate that this species presents clinical effectiveness on neurological disorders. Hence, A. catechu extracts could be used as a bioactive ingredient for functional food, nutraceuticals, or cosmeceuticals. However, further studies, especially extensive and comprehensive clinical trials, are recommended for the use of Areca in the treatment of diseases.

Cellular apoptosis and necrosis as therapeutic targets for novel Eugenol Tosylate Congeners against Candida albicans.

Despite the rise of new Candida species, Candida albicans tops the list with high morbidity and mortality rates. To tackle this problem there is a need to explore new antifungals that could replace or augment the current treatment options. We previously reported that tosylation of eugenol on hydroxyl group resulted in molecules with enhanced antifungal potency. In line with that work, we synthesized new eugenol tosylate congeners (ETC-1-ETC-7) with different substituents on pendent sulfonyl group and tested their susceptibility against different fluconazole susceptible and resistant C. albicans strains. We evaluated physiology and mode of cell death in response to the most active derivatives by analyzing major apoptotic markers in yeast such as phosphatidylserine externalization, DNA fragmentation, mitochondrial depolarization and decrease in cytochrome c oxidase activity. The results demonstrated that all C. albicans strains were variably susceptible to the test compounds with MIC ranging from 0.125-512 µg/ml, and the most active compounds (ETC-5, ETC-6 and ETC-7) actuate apoptosis and necrosis in Candida cells in a dose-dependent manner via metacaspase-dependent pathway. Furthermore haemolytic assay showed low cytotoxicity effect of these ETCs. Overall the results indicated that ETCs exhibit potential antifungal activity against C. albicans by activating apoptotic and necrotic pathways.