Antibody Response against Severe Acute Respiratory Syndrome Coronavirus 2 Messenger Ribonucleic Acid Vaccines in Infected Individuals: A Systematic Review

Individuals with a history of coronavirus disease 2019 (COVID-19) exhibit memory immunity acquired during natural infection. However, a decline in immunity after infection renders these individuals vulnerable to re-infection, in addition to a higher risk of infection with new variants. This systematic review examined related studies to elucidate the antibody response in these infected individuals after messenger ribonucleic acid (mRNA) vaccination. Hence, the focus of this review was to ascertain differences in the concentration of binding and neutralising antibodies of previously infected individuals in comparison to those of infection-naïve individuals after administration of two doses of mRNA vaccination through available case-control and cohort studies. Positive reverse transcriptase-polymerase chain reaction (RT-PCR) test or detectable anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies at the baseline in included studies showed categorisation of infected and uninfected individuals. This review utilised three online databases: PubMed, Scopus and Cochrane with the following keywords: (COVID-19 OR 'Coronavirus Disease 2019' OR SARS-CoV-2) AND Immun* AND (Pfizer OR BioNTech OR BNT162b2 OR Comirnaty OR Moderna OR mRNA-1273) from January 2019 to July 2021. Following the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocol (PRISMA-P) 2020 guidelines and assessment based on the Crowe Critical Appraisal Tool (CCAT), we included 13 related qualified papers of observational studies discerning the binding and neutralising antibody concentrations of infected and uninfected individuals after administration of mRNA vaccines, such as the BNT162b2 and mRNA-1273 vaccine. The mRNA vaccines induced robust binding and neutralising antibody responses in both groups. However, infected individuals showed induction of higher antibody responses in a shorter time compared to uninfected individuals. Hence, a single dose of mRNA vaccination for infected individuals may be sufficient to reach the same level of antibody concentration as that observed in uninfected individuals after receiving two doses of vaccination.

Genetic Manipulation Strategies for β-Thalassemia: A Review

Thalassemias are monogenic hematologic diseases that are classified as α- or β-thalassemia according to its quantitative abnormalities of adult α- or β-globin chains. β-thalassemia has widely spread throughout the world especially in Mediterranean countries, the Middle East, Central Asia, India, Southern China, and the Far East as well as countries along the north coast of Africa and in South America. The one and the only cure for β-thalassemia is allogenic hematopoietic stem cell transplantations (HSCT). Nevertheless, the difficulty to find matched donors has hindered the availability of this therapeutic option. Therefore, this present review explored the alternatives for β-thalassemia treatment such as RNA manipulation therapy, splice-switching, genome editing and generation of corrected induced pluripotent stem cells (iPSCs). Manipulation of β-globin RNA is mediated by antisense oligonucleotides (ASOs) or splice-switching oligonucleotides (SSOs), which redirect pre-mRNA splicing to significantly restore correct β-globin pre-mRNA splicing and gene product in cultured erythropoietic cells. Zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs) and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9) are designer proteins that can alter the genome precisely by creating specific DNA double-strand breaks. The treatment of β-thalassemia patient-derived iPSCs with TALENs have been found to correct the β-globin gene mutations, implying that TALENs could be used as a therapy option for β-thalassemia. Additionally, CRISPR technologies using Cas9 have been used to fix mutations in the β-globin gene in cultured cells as well as induction of hereditary persistence of fetal hemoglobin (HPFH), and α-globin gene deletions have proposed a possible therapeutic option for β-thalassemia. Overall, the accumulated research evidence demonstrated the potential of ASOs-mediated aberrant splicing correction of β-thalassemia mutations and the advancements of genome therapy approaches using ZFNs, TALENs, and CRISPR/Cas9 that provided insights in finding the permanent cure of β-thalassemia.

An In Vitro Anticancer Activity Evaluation of Neolamarckia cadamba (Roxb.) Bosser Leaves' Extract and its Metabolite Profile

The leaves of Neolamarckia cadamba (NC) (Roxb.) Bosser (family: Rubiaceae) are traditionally used to treat breast cancer in Malaysia; however, this traditional claim is yet to be scientifically verified. Hence, this study was aimed to evaluate the anticancer effect of NC leaves' ethanol extract against breast cancer cell line (MCF-7 cells) using an in vitro cell viability, cytotoxicity, and gene expression assays followed by the gas chromatography analysis to further confirm active principles. Results revealed 0.2 mg/ml as the half maximal inhibitory concentration (IC₅₀) against MCF-7. The extract exerted anticancer effect against MCF-7 cells in a dose- and time-dependent manner. The cell cycle assay showed that the extract arrested MCF-7 cells in the G0/G1 phase, and apoptosis was observed after 72 h by the Annexin-V assay. The gene expression assay revealed that the cell cycle arrest was associated with the downregulation of CDK2 and subsequent upregulation of p21 and cyclin E. The extract induced apoptosis via the mediation of the mitochondrial cell death pathways. A chromatography analysis revealed the contribution of D-pinitol and myo-inositol as the two major bioactive compounds to the activity observed. Overall, the study demonstrated that NC leaves' ethanol extract exerts anticancer effect against MCF-7 human breast cancer cells through the induction of apoptosis and cell cycle arrest, thereby justifying its traditional use for the treatment of breast cancer in Malaysia.

Streptococcus salivarius K12 inhibits Candida albicans aggregation, biofilm formation and dimorphism

Candida albicans causes candidiasis, particularly in immunocompromised patients. Streptococcus salivarius K12 (K12) is a probiotic isolated from a healthy oral cavity. The study aimed to determine the effect of K12 on C. albicans aggregation, biofilm formation and dimorphism. C. albicans ATCC MYA-4901, acquired immunodeficiency syndrome (AIDS) isolate (ALC2), and oral cancer isolate (ALC3) and K12 were used in the study. All C. albicans strains and K12 were grown in yeast peptone dextrose agar and brain heart infusion agar, respectively, prior to aggregation, biofilm and dimorphism assays. Auto-aggregation of C. albicans MYA-4901 and ALC2 was categorised as high, while the co-aggregation of the strains was low in the presence of K12. C. albicans total cell count decreased significantly when co-cultured with K12 compared with monocultured C. albicans biofilm (p < 0.05). Inhibition of yeast-to-hyphae transition was also observed when co-cultured with K12. In conclusion, K12 inhibits C. albicans aggregation, biofilm formation and dimorphism.

Epigenetic Insights and Potential Modifiers as Therapeutic Targets in β-Thalassemia

Thalassemia, an inherited quantitative globin disorder, consists of two types, α- and β-thalassemia. β-thalassemia is a heterogeneous disease that can be asymptomatic, mild, or even severe. Considerable research has focused on investigating its underlying etiology. These studies found that DNA hypomethylation in the β-globin gene cluster is significantly related to fetal hemoglobin (HbF) elevation. Histone modification reactivates γ-globin gene expression in adults and increases β-globin expression. Down-regulation of γ-globin suppressor genes, i.e., BCL11A, KLF1, HBG-XMN1, HBS1L-MYB, and SOX6, elevates the HbF level. β-thalassemia severity is predictable through FLT1, ARG2, NOS2A, and MAP3K5 gene expression. NOS2A and MAP3K5 may predict the β-thalassemia patient's response to hydroxyurea, a HbF-inducing drug. The transcription factors NRF2 and BACH1 work with antioxidant enzymes, i.e., PRDX1, PRDX2, TRX1, and SOD1, to protect erythrocytes from oxidative damage, thus increasing their lifespan. A single β-thalassemia-causing mutation can result in different phenotypes, and these are predictable by IGSF4 and LARP2 methylation as well as long non-coding RNA expression levels. Finally, the coinheritance of β-thalassemia with α-thalassemia ameliorates the β-thalassemia clinical presentation. In conclusion, the management of β-thalassemia is currently limited to genetic and epigenetic approaches, and numerous factors should be further explored in the future.

Cytotoxicity and Toxicological Studies of Artocarpus altilis Extracts, Inducing Apoptosis and Cell Cycle Arrest via CASPASE-3 and CASPASE-8 Pathways Against Human Breast MCF-7 Cells

In recent biomedical research, the area of cancer and infectious diseases has a leading position in the utilization of medicinal plants as a source of drug discovery. Malaysia has a diversity and a large number of underutilized fruits that are rich in phenolic compounds. Artoarpus altilis consider an underutilized fruit that is rich in phenolic compounds. Methanol extracts of A. altilis have been previously found to contain a high content of antioxidant phytochemicals. The purpose of the study was to evaluate the cytotoxicity and toxicological effect of methanol fruit extracts against MCF-7 cells. To determine the least concentration that might kill or suppress the growth of the cancer cells was in a concentration-dependent manner approach. The variation in the cytotoxic activity among the extracts was indicated by determining the IC50 of each extract against cells at 72 h. The IC50 of the samples was measured using a trypan blue exclusion assay. The methanol extract of the pulp part showed the least inhibition concentration of 15.40±0.91 μg/mL on MCF-7 cells. In the study, the molecular mechanism of methanol extracts-induced apoptosis and cell cycle arrested in human cancer cells were investigated in a time-dependent-manners approach by using flow cytometry. The treated cells were stained with nexin to detect early and late apoptosis and with propidium iodide (PI) for cell cycle arrest associated with the DNA fragmentation, various cell arrests occurred at G1/S, S, and G2/M phases. Lastly, the gene expression analysis by (RT-qPCR) method was carried out by analyzing the expression of the gene of interest for the quantification of mRNA levels. Results after cells treated with IC50 were revealed by upregulating anti-apoptotic genes/downregulated of pro-apoptotic BCL-2 gene expressions were triggered the treated cells into CASPASE-3, intrinsic and extrinsic pathways. These findings suggest that the methanol extracts of three parts of A. altilis fruit have potential anticancer activity against MCF-7 cells mainly the pulp part of the fruit.

Determination toxic effects of Hystrix Brachyura Bezoar extracts using cancer cell lines and embryo zebrafish (Danio rerio) models and identification of active principles through GC-MS analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Porcupine bezoar (PB) is used as folk medicine for various medical conditions including cancer treatment in Malaysia. However, its toxicity profile has never been thoroughly ascertained to confirm its safe nature as an efficacious traditional medicine in the treatment of cancer as well as other ailments.

AIM OF THE STUDY

This study was aimed to reveal three different PBs' aqueous extracts(viz. PB-A, PB-B, PB-C) chemical constituent's profile using GC-MS analysis, anticancer property on A375, HeLa and MCF7 cancer cells, toxicity profile on zebrafish embryo morphology, EC₅₀, LC₅₀ and teratogenicity index.

MATERIALS AND METHODS

PBs' extracts characterization was performed through GC-MS analysis, in vitro anticancer effect was carried out on A375, HeLa and MCF7 cancer cell lines and finally and toxicity properties on three different PBs aqueous extracts (viz. PB-A, PB-B, PB-C) were determined using zebrafish embryo model.

RESULTS

The GC-MS analysis revealed 10 similar compounds in all PBs' extracts. Dilauryl thiodipropionate was found to be a major compound in all PBs' extracts followed by tetradecanoic acid. An in vitro anticancer study revealed PB extracts exerted median inhibition concentration (IC₅₀) <50 μg/mL, on cancer cells viz. A375, HeLa and MCF7 with no significant toxicity on normal cells viz. NHDF cells. In vivo toxicity of PBs extracts found affecting tail detachment, hatching, craniofacial, brain morphology, soft tissues, edema, spinal, somites, notochord and cardiovascular system (brachycardia, disruption of blood circulation) deformities. The LC₅₀ and EC₅₀ demonstrated PB extracts effect as dose and time dependent with median concentration <150.0 μg/mL. Additionally, teratogenicity index (TI) viz. >1.0 revealed teratogenic property for PB extracts.

CONCLUSIONS

The findings revealed that all three PBs aqueous extracts possessed anticancer activity and exhibited significant toxicological effects on zebrafish embryos with high teratogenicity index. Hence, its use as an anticancer agent requires further investigation and medical attentions to determine its safe dose.

The nipple-areolar complex: comprehensive imaging review

The nipple-areolar complex can be affected by a variety of benign and malignant entities that can present with non-specific symptoms. Benign pathologies commonly affecting the nipple-areolar complex include nipple calcifications, nipple adenoma, abscess of Montgomery tubercles, ductal ectasia, periductal mastitis, and papilloma. Malignant pathologies that affect the nipple-areolar complex include Paget's disease of the breast, ductal carcinoma in-situ, and invasive ductal carcinoma. Clinical history and examination, imaging, and tissue sampling when appropriate are co-dependent factors that guide the assessment of nipple-areolar pathologies. This article provides a review of the normal anatomy, common anatomical variants, benign and malignant pathologies, and imaging techniques to guide the diagnostic assessment of the nipple-areolar complex.

The role of Candida albicans candidalysin ECE1 gene in oral carcinogenesis

Oral squamous cell carcinoma is associated with many known risk factors including tobacco smoking, chronic alcoholism, poor oral hygiene, unhealthy dietary habits and microbial infection. Previous studies have highlighted Candida albicans host tissue infection as a risk factor in the initiation and progression of oral cancer. C albicans invasion induces several cancerous hallmarks, such as activation of proto-oncogenes, induction of DNA damage and overexpression of inflammatory signalling pathways. However, the molecular mechanisms behind these responses remain unclear. A recently discovered fungal toxin peptide, candidalysin, has been reported as an essential molecule in epithelial damage and host recognition of C albicans infection. Candidalysin has a clear role in inflammasome activation and induction of cell damage. Several inflammatory molecules such as IL-6, IL-17, NLRP3 and GM-CSF have been linked to carcinogenesis. Candidalysin is encoded by the ECE1 gene, which has been linked to virulence factors of C albicans such as adhesion, biofilm formation and filamentation properties. This review discusses the recent epidemiological burden of oral cancer and highlights the significance of the ECE1 gene and the ECE1 protein breakdown product, candidalysin in oral malignancy. The immunological and molecular mechanisms behind oral malignancy induced by inflammation and the role of the toxic fungal peptide candidalysin in oral carcinogenesis are explored. With increasing evidence associating C albicans with oral carcinoma, identifying the possible fungal pathogenicity factors including the role of candidalysin can assist in efforts to understand the link between C albicans infection and carcinogenesis, and pave the way for research into therapeutic potentials.

The Effect of Oral Probiotic Streptococcus Salivarius K12 on Candida Albicans Biofilm Formation

Introduction:  Oral cancer is the sixth most common cancer worldwide with  Candida albicans  infection being one of the aetiological factors for the disease. Meanwhile,  Streptococcus salivarius  K12 is an oral probiotic that is beneficial to the oral cavity. The objective of the present study is to determine the effect of  S. salivarius  K12 on  C. albicans  biofilm-forming ability with the hypothesis that  S. salivarius  K12 inhibits biofilm formation of  C. albicans  Materials and method: To assess the effect of  S. salivarius  K12 on  C. albicans  biofilm formation,  S. salivarius  K12, lab strain  C. albicans  MYA-4901 and clinical isolates from oral cancer, ALC2 and ALC3 were grown in both nutrient broth (NB) and RPMI. In a mono-species biofilm, 105 of  C. albicans  cells and 106 of  S. salivarius  K12 cells were grown separately in a 96-well plate. In contrast, both microorganisms were combined for polymicrobial biofilms with similar cell numbers as in mono-species. The biofilms were incubated for 72 hours at 37°C and the media were replenished every 24 hours. Finally, the crystal violet assay was conducted, and the optical density was measured at OD620nm.  Results: Polymicrobial biofilms of  C. albicans  (MYA-4901 and ALC3) with  S. salivarius K12 when grown in NB, exhibited a decrease by 64.5 ± 25.8% and 83.7 ± 5.4%, respectively when compared to the expected biofilms which were predominated by yeast form.  Furthermore, polymicrobial biofilms of  C. albicans  (ALC2 and ALC3) with  S. salivarius  K12 showed a decrease by 62.5 ± 25.6% and 55.9 ± 17.1 %, respectively when compared to the expected biofilms when grown in RPMI that were predominated by hyphal form.  Conclusion:  S. salivarius  K12 inhibited polymicrobial biofilms formation of  C. albicans  yeast and hyphal forms, thus supported the hypothesis that  S. salivarius  K12 inhibits biofilm formation of  C. albicans.

Optimization of Hyperglycemic Induction in Zebrafish and Evaluation of Its Blood Glucose Level and Metabolite Fingerprint Treated with Psychotria malayana Jack Leaf Extract

A standard protocol to develop type 1 diabetes in zebrafish is still uncertain due to unpredictable factors. In this study, an optimized protocol was developed and used to evaluate the anti-diabetic activity of Psychotria malayana leaf. The aims of this study were to develop a type 1 diabetic adult zebrafish model and to evaluate the anti-diabetic activity of the plant extract on the developed model. The ability of streptozotocin and alloxan at a different dose to elevate the blood glucose levels in zebrafish was evaluated. While the anti-diabetic activity of P. malayana aqueous extract was evaluated through analysis of blood glucose and LC-MS analysis fingerprinting. The results indicated that a single intraperitoneal injection of 300 mg/kg alloxan was the optimal dose to elevate the fasting blood glucose in zebrafish. Furthermore, the plant extract at 1, 2, and 3 g/kg significantly reduced blood glucose levels in the diabetic zebrafish. In addition, LC-MS-based fingerprinting indicated that 3 g/kg plant extract more effective than other doses. Phytosterols, sugar alcohols, sugar acid, free fatty acids, cyclitols, phenolics, and alkaloid were detected in the extract using GC-MS. In conclusion, P. malayana leaf aqueous extract showed anti-diabetic activity on the developed type 1 diabetic zebrafish model.

Occurrence of Intestinal Parasitic Contamination in Select Consumed Local Raw Vegetables and Fruits in Kuantan, Pahang

Intestinal parasitic infections are one of the most common causes of human diseases that result in serious health and economic issues in many developing and developed countries. Raw vegetables and fruits play an important role in transmitting parasites to humans. Hence, the aim of this study was to investigate the parasitological contamination of select commonly consumed local leafy vegetables and fruits in Kuantan, Malaysia. One kilogram of locally consumed raw vegetables and fruits were collected randomly from the Kuantan wet market (Pasar Tani) during the monsoon season (November 2014-January 2015) and the dry season (February 2015-April 2015). A standard wet mount procedure and modified Ziehl-Neelsen staining were used for the detection of parasites. In the present study, the examination of vegetables revealed five different parasite species. The vegetable samples collected from Kuantan's wet market were positive for both helminthes and protozoa. However, the fruits samples were negative for parasitic contamination. Pegaga was the most contaminated leafy vegetable in this study, and Strongyloides was the parasite found most frequently. Furthermore, there was a high diversity in the type of parasites observed during the dry season compared to the monsoon season. Therefore, further action should be taken to reduce the occurrence of parasitic contamination in vegetables by implementing the principles of good agricultural practice and improving water treatment efficacy.

Identification of Cryptosporidium from Dairy Cattle in Pahang, Malaysia

Cryptosporidium, a protozoan parasite, can cause cryptosporidiosis which is a gastrointestinal disease that can infect humans and livestock. Cattle are the most common livestock that can be infected with this protozoan. This study was carried out to determine the prevalence of Cryptosporidium infection in cattle in Kuantan, Pahang, Malaysia and to find out the association between the occurrence of infection and 3 different ages of cattle (calves less than 1 year, yearling, and adult cattle). The samples were processed by using formol-ether concentration technique and stained by modified Ziehl Neelsen. The results showed that 15.9% (24/151) of cattle were positive for Cryptosporidium oocysts. The occurrence of Cryptosporidium in calves less than 1 year was the highest with the percentage of 20.0% (11/55) followed by yearling and adult cattle, with the percentage occurrence of 15.6 % (7/45) and 11.8% (6/51), respectively. There was no significant association between the occurrence and age of cattle and presence of diarrhea. Good management practices and proper hygiene management must be taken in order to reduce the infection. It is highly important to control the infection since infected cattle may serve as potential reservoirs of the infection to other animals and humans, especially animal handlers.

Abstract B73: Chemopreventive effect of Streblus asper, a bonsai plant, on osteosarcoma cells: A preliminary study

Epidemiological studies have demonstrated a positive correlation between consumption of vegetables, fruits and beverages with reduced risk of cancer. It is estimated there are around 8,100 plant species in the Malaysian rain forests, with 10% of them reported to have some medicinal value. However, to date in Malaysia, not much investigation has been done on chemopreventive activities on cancer although Malaysian plants are an exclusive source of effective chemopreventive agents and therefore, this background leads to the premise that our local plants such as Streblus asper could have greater potential for the chemoprevention activities. Streblus asper is well known as an expensive bonsai plant which is indigenous to tropical countries such as Malaysia, Thailand, Sri Lanka and India. It is used traditionally in leprosy, piles, diarrhea, dysentery, elephantiasis and cancer. It finds place in Ayurvedic Pharmacopoeia of India and also been described in some monographs, but none have reported its activity as chemopreventive agents and the underlying mechanisms remain unclear. In the present study, we try to identify its biological properties and the cytotoxicity effect on normal liver and kidney cells. Using the osteosarcoma cells as our in vitro model, the IC50 of Streblus asper root extract was determined and observed its effect on the osteosarcoma cells morphology that changes within time, the anti-proliferative pattern and live-death analysis under confocal microscope analysis. The results showed that the root extracts did not contained any heavy metals compound such as mercury and cadmium and with less arsenic (0.02 ppm) and plumbum (0.07 ppm) and showing non-cytotoxic effect on vero cells (normal kidney cells) and WRL-68 cells (normal liver cells). Our HPLC profiling analysis also revealed antioxidants compounds exist in the Streblus asper root extracts such as caffeic acid which has been shown to act as a carcinogenic inhibitor. Although the low-level of anti-oxidants been found from the extracts but it still can inhibit the growth of the osteosarcoma cells which also exert apoptosis features like cell shrinkage (atrophy) and vocalization in time and dose-dependent manner. The plant extracts IC50 doses was at 0.05% of root extracts and it also demonstrated the anti-proliferative effect by suppressed the cells growth as early as 12 hours of treatment and marked cell death till day 6. On live-death analysis under confocal microscope using Calcein and Ethidium staining confirmed that Streblus asper root extract exert cell death to osteosarsoma cells. This study is just a preliminary study as to identify its pharmacological properties on carcinogenesis and further investigation is still on-going to develop it as the chemopreventive agent especially to determine the signaling pathway involved.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B73.