Is ChatGPT 'ready' to be a learning tool for medical undergraduates and will it perform equally in different subjects? Comparative study of ChatGPT performance in tutorial and case-based learning questions in physiology and biochemistry.

PURPOSE: Generative AI will become an integral part of education in future. The potential of this technology in different disciplines should be identified to promote effective adoption. This study evaluated the performance of ChatGPT in tutorial and case-based learning questions in physiology and biochemistry for medical undergraduates. Our study mainly focused on the performance of GPT-3.5 version while a subgroup was comparatively assessed on GPT-3.5 and GPT-4 performances. MATERIALS AND METHODS: Answers were generated in GPT-3.5 for 44 modified essay questions (MEQs) in physiology and 43 MEQs in biochemistry. Each answer was graded by two independent examiners. Subsequently, a subset of 15 questions from each subject were selected to represent different score categories of the GPT-3.5 answers; responses were generated in GPT-4, and graded. RESULTS: The mean score for physiology answers was 74.7 (SD 25.96). GPT-3.5 demonstrated a statistically significant (p = .009) superior performance in lower-order questions of Bloom's taxonomy in comparison to higher-order questions. Deficiencies in the application of physiological principles in clinical context were noted as a drawback. Scores in biochemistry were relatively lower with a mean score of 59.3 (SD 26.9) for GPT-3.5. There was no statistically significant difference in the scores for higher and lower-order questions of Bloom's taxonomy. The deficiencies highlighted were lack of in-depth explanations and precision. The subset of questions where the GPT-4 and GPT-3.5 were compared demonstrated a better overall performance in GPT-4 responses in both subjects. This difference between the GPT-3.5 and GPT-4 performance was statistically significant in biochemistry but not in physiology. CONCLUSIONS: The differences in performance across the two versions, GPT-3.5 and GPT-4 across the disciplines are noteworthy. Educators and students should understand the strengths and limitations of this technology in different fields to effectively integrate this technology into teaching and learning.

O-GlcNAcylation promotes fatty acid synthase activity under nutritional stress as a pro-survival mechanism in cancer cells.

Protein O-GlcNAcylation is a specific form of protein glycosylation that targets a wide range of proteins with important functions. O-GlcNAcylation is known to be deregulated in cancer and has been linked to multiple aspects of cancer pathology. Despite its ubiquity and importance, the current understanding of the role of O-GlcNAcylation in the stress response remains limited. In this study, we performed a quantitative chemical proteomics-based open study of the O-GlcNAcome in HeLa cells, and identified 163 differentially-glycosylated proteins under starvation, involving multiple metabolic pathways. Among them, fatty acid metabolism was found to be targeted and subsequent analysis confirmed that fatty acid synthase (FASN) is O-GlcNAcylated. O-GlcNAcylation led to enhanced de novo fatty acid synthesis (FAS) activity, and fatty acids contributed to the cytoprotective effects of O-GlcNAcylation under starvation. Moreover, dual inhibition of O-GlcNAcylation and FASN displayed a strong synergistic effect in vitro in inducing cell death in cancer cells. Together, the results from this study provide novel insights into the role of O-GlcNAcylation in the nutritional stress response and suggest the potential of combining inhibition of O-GlcNAcylation and FAS in cancer therapy.

Development and validation of a serum microRNA biomarker panel for detecting gastric cancer in a high-risk population.

OBJECTIVE: An unmet need exists for a non-invasive biomarker assay to aid gastric cancer diagnosis. We aimed to develop a serum microRNA (miRNA) panel for identifying patients with all stages of gastric cancer from a high-risk population. DESIGN: We conducted a three-phase, multicentre study comprising 5248 subjects from Singapore and Korea. Biomarker discovery and verification phases were done through comprehensive serum miRNA profiling and multivariant analysis of 578 miRNA candidates in retrospective cohorts of 682 subjects. A clinical assay was developed and validated in a prospective cohort of 4566 symptomatic subjects who underwent endoscopy. Assay performance was confirmed with histological diagnosis and compared with Helicobacter pylori (HP) serology, serum pepsinogens (PGs), 'ABC' method, carcinoembryonic antigen (CEA) and cancer antigen 19-9 (CA19-9). Cost-effectiveness was analysed using a Markov decision model. RESULTS: We developed a clinical assay for detection of gastric cancer based on a 12-miRNA biomarker panel. The 12-miRNA panel had area under the curve (AUC)=0.93 (95% CI 0.90 to 0.95) and AUC=0.92 (95% CI 0.88 to 0.96) in the discovery and verification cohorts, respectively. In the prospective study, overall sensitivity was 87.0% (95% CI 79.4% to 92.5%) at specificity of 68.4% (95% CI 67.0% to 69.8%). AUC was 0.848 (95% CI 0.81 to 0.88), higher than HP serology (0.635), PG 1/2 ratio (0.641), PG index (0.576), ABC method (0.647), CEA (0.576) and CA19-9 (0.595). The number needed to screen is 489 annually. It is cost-effective for mass screening relative to current practice (incremental cost-effectiveness ratio=US$44 531/quality-of-life year). CONCLUSION: We developed and validated a serum 12-miRNA biomarker assay, which may be a cost-effective risk assessment for gastric cancer. TRIAL REGISTRATION NUMBER: This study is registered with ClinicalTrials.gov (Registration number: NCT04329299).

Targeting autophagy using natural compounds for cancer prevention and therapy.

Autophagy, also known as macroautophagy, is a tightly regulated process involved in the stress responses, such as starvation. It is a vacuolar, lysosomal pathway for the degradation of damaged proteins and organelles in eukaryotic cells. Autophagy also plays a key role in various tissue processes and immune responses and in the regulation of inflammation. Over the past decade, three levels of autophagy regulation have been identified in mammalian cells: 1) signaling, 2) autophagosome formation, and 3) autophagosome maturation and lysosomal degradation. Any deregulation of the autophagy processes can lead to the development of diverse chronic diseases, such as diabetes, obesity, cardiovascular disease, neurodegenerative disease, and malignancies. However, the potential role of autophagy in cancer is rather complex and has been associated with both the induction and the inhibition of neoplasia. Several synthetic autophagy modulators have been identified as promising candidates for cancer therapy. In addition, diverse phytochemicals derived from natural sources, such as curcumin, ursolic acid, resveratrol, thymoquinone, and γ-tocotrienol, also have attracted attention as promising autophagy modulators with minimal side effects. In this review, the authors discuss the importance of autophagy regulators and various natural compounds that induce and/or inhibit autophagy in the prevention and therapy of cancer.

Reed-Sternberg cell-derived lymphotoxin-α activates endothelial cells to enhance T-cell recruitment in classical Hodgkin lymphoma.

It is known that cells within the inflammatory background in classical Hodgkin lymphoma (cHL) provide signals essential for the continual survival of the neoplastic Hodgkin and Reed-Sternberg (HRS) cells. However, the mechanisms underlying the recruitment of this inflammatory infiltrate into the involved lymph nodes are less well understood. In this study, we show in vitro that HRS cells secrete lymphotoxin-α (LTα) which acts on endothelial cells to upregulate the expression of adhesion molecules that are important for T cell recruitment. LTα also enhances the expression of hyaluronan which preferentially contributes to the recruitment of CD4(+) CD45RA(+) naïve T cells under in vitro defined flow conditions. Enhanced expression of LTα in HRS cells and tissue stroma; and hyaluronan on endothelial cells are readily detected in involved lymph nodes from cHL patients. Our study also shows that although NF-κB and AP-1 are involved, the cyclooxygenase (COX) pathway is the dominant regulator of LTα production in HRS cells. Using pharmacological inhibitors, our data suggest that activity of COX1, but not of COX2, directly regulates the expression of nuclear c-Fos in HRS cells. Our findings suggest that HRS cell-derived LTα is an important mediator that contributes to T cell recruitment into lesional lymph nodes in cHL.

Heat-shock protein 60 translocates to the surface of apoptotic cells and differentiated megakaryocytes and stimulates phagocytosis.

Heat-shock protein 60 (Hsp60) is a highly conserved stress protein which has chaperone functions in prokaryotes and mammalian cells. Hsp60 is associated with the mitochondria and the plasma membrane through phosphorylation by protein kinase A, and is incorporated into lipid membranes as a protein-folding chaperone. Its diverse intracellular chaperone functions include the secretion of proteins where it maintains the conformation of precursors and facilitates their translocation through the plasma membrane. We report here that Hsp60 is concentrated in apoptotic membrane blebs and translocates to the surface of cells undergoing apoptosis. Hsp60 is also enriched in platelets derived from terminally differentiated megakaryocytes and expressed at the surface of senescent platelets. Furthermore, the exposure of monocytic U937 cells to Hsp60 enhanced their phagocytic activity. Our results suggests that externalized Hsp60 in apoptotic cells and senescent platelets influences events subsequent to apoptosis, such as the clearance of apoptotic cells by phagocytes.

PI3K/AKT Signaling Tips the Balance of Cytoskeletal Forces for Cancer Progression.

The PI3K/AKT signaling pathway plays essential roles in multiple cellular processes, which include cell growth, survival, metabolism, and motility. In response to internal and external stimuli, the PI3K/AKT signaling pathway co-opts other signaling pathways, cellular components, and cytoskeletal proteins to reshape individual cells. The cytoskeletal network comprises three main components, which are namely the microfilaments, microtubules, and intermediate filaments. Collectively, they are essential for many fundamental structures and cellular processes. In cancer, aberrant activation of the PI3K/AKT signaling cascade and alteration of cytoskeletal structures have been observed to be highly prevalent, and eventually contribute to many cancer hallmarks. Due to their critical roles in tumor progression, pharmacological agents targeting PI3K/AKT, along with cytoskeletal components, have been developed for better intervention strategies against cancer. In our review, we first discuss existing evidence in-depth and then build on recent advances to propose new directions for therapeutic intervention.

Cytoskeletal Dynamics in Epithelial-Mesenchymal Transition: Insights into Therapeutic Targets for Cancer Metastasis.

In cancer cells, a vital cellular process during metastasis is the transformation of epithelial cells towards motile mesenchymal cells called the epithelial to mesenchymal transition (EMT). The cytoskeleton is an active network of three intracellular filaments: actin cytoskeleton, microtubules, and intermediate filaments. These filaments play a central role in the structural design and cell behavior and are necessary for EMT. During EMT, epithelial cells undergo a cellular transformation as manifested by cell elongation, migration, and invasion, coordinated by actin cytoskeleton reorganization. The actin cytoskeleton is an extremely dynamic structure, controlled by a balance of assembly and disassembly of actin filaments. Actin-binding proteins regulate the process of actin polymerization and depolymerization. Microtubule reorganization also plays an important role in cell migration and polarization. Intermediate filaments are rearranged, switching to a vimentin-rich network, and this protein is used as a marker for a mesenchymal cell. Hence, targeting EMT by regulating the activities of their key components may be a potential solution to metastasis. This review summarizes the research done on the physiological functions of the cytoskeleton, its role in the EMT process, and its effect on multidrug-resistant (MDR) cancer cells-highlight some future perspectives in cancer therapy by targeting cytoskeleton.

Putting the BRK on breast cancer: From molecular target to therapeutics.

BReast tumor Kinase (BRK, also known as PTK6) is a non-receptor tyrosine kinase that is highly expressed in breast carcinomas while having low expression in the normal mammary gland, which hints at the oncogenic nature of this kinase in breast cancer. In the past twenty-six years since the discovery of BRK, an increasing number of studies have strived to understand the cellular roles of BRK in breast cancer. Since then, BRK has been found both in vitro and in vivo to activate a multitude of oncoproteins to promote cell proliferation, metastasis, and cancer development. The compelling evidence concerning the oncogenic roles of BRK has also led, since then, to the rapid and exponential development of inhibitors against BRK. This review highlights recent advances in BRK biology in contributing to the "hallmarks of cancer", as well as BRK's therapeutic significance. Importantly, this review consolidates all known inhibitors of BRK activity and highlights the connection between drug action and BRK-mediated effects. Despite the volume of inhibitors designed against BRK, none have progressed into clinical phase. Understanding the successes and challenges of these inhibitor developments are crucial for the future improvements of new inhibitors that can be clinically relevant.

Involvement of STAT5 in Oncogenesis.

Signal transducer and activator of transcription (STAT) proteins, and in particular STAT3, have been established as heavily implicated in cancer. Recently, the involvement of STAT5 signalling in the pathology of cancer has been shown to be of increasing importance. STAT5 plays a crucial role in the development of the mammary gland and the homeostasis of the immune system. However, in various cancers, aberrant STAT5 signalling promotes the expression of target genes, such as cyclin D, Bcl-2 and MMP-2, that result in increased cell proliferation, survival and metastasis. To target constitutive STAT5 signalling in cancers, there are several STAT5 inhibitors that can prevent STAT5 phosphorylation, dimerisation, or its transcriptional activity. Tyrosine kinase inhibitors (TKIs) that target molecules upstream of STAT5 could also be utilised. Consequently, since STAT5 contributes to tumour aggressiveness and cancer progression, inhibiting STAT5 constitutive activation in cancers that rely on its signalling makes for a promising targeted treatment option.

Cytoskeletal Proteins in Cancer and Intracellular Stress: A Therapeutic Perspective.

Cytoskeletal proteins, which consist of different sub-families of proteins including microtubules, actin and intermediate filaments, are essential for survival and cellular processes in both normal as well as cancer cells. However, in cancer cells, these mechanisms can be altered to promote tumour development and progression, whereby the functions of cytoskeletal proteins are co-opted to facilitate increased migrative and invasive capabilities, proliferation, as well as resistance to cellular and environmental stresses. Herein, we discuss the cytoskeletal responses to important intracellular stresses (such as mitochondrial, endoplasmic reticulum and oxidative stresses), and delineate the consequences of these responses, including effects on oncogenic signalling. In addition, we elaborate how the cytoskeleton and its associated molecules present themselves as therapeutic targets. The potential and limitations of targeting new classes of cytoskeletal proteins are also explored, in the context of developing novel strategies that impact cancer progression.

Autophagy Modulators: Mechanistic Aspects and Drug Delivery Systems.

Autophagy modulation is considered to be a promising programmed cell death mechanism to prevent and cure a great number of disorders and diseases. The crucial step in designing an effective therapeutic approach is to understand the correct and accurate causes of diseases and to understand whether autophagy plays a cytoprotective or cytotoxic/cytostatic role in the progression and prevention of disease. This knowledge will help scientists find approaches to manipulate tumor and pathologic cells in order to enhance cellular sensitivity to therapeutics and treat them. Although some conventional therapeutics suffer from poor solubility, bioavailability and controlled release mechanisms, it appears that novel nanoplatforms overcome these obstacles and have led to the design of a theranostic-controlled drug release system with high solubility and active targeting and stimuli-responsive potentials. In this review, we discuss autophagy modulators-related signaling pathways and some of the drug delivery strategies that have been applied to the field of therapeutic application of autophagy modulators. Moreover, we describe how therapeutics will target various steps of the autophagic machinery. Furthermore, nano drug delivery platforms for autophagy targeting and co-delivery of autophagy modulators with chemotherapeutics/siRNA, are also discussed.

Characterization of Numb expression in astrocytomas.

During early neurodevelopment, asymmetric segregation of Numb in mitotic progenitor cells influences the fate of daughter cells, whereby one daughter retains the progenitor phenotype while the other proceeds along a differentiation pathway. Numb has also been reported to function as a tumor suppressor in breast cancers and medulloblastomas. Given its role in maintaining neural progenitor pools in animal models and its reported role as a tumor suppressor, Numb could potentially contribute to astrocytoma oncogenesis. We characterized Numb expression in both human astrocytoma tissue samples and glioblastoma cell lines. We found that Numb is expressed in all grades of astrocytomas, being predominantly cytoplasmic in higher-grade astrocytomas but nuclear in pilocytic astrocytomas. Numb is also present in normal neurons, but not in normal astrocytes. In cultured glioblastoma cells, Numb concentrates in the perinuclear region and process tips. Numb expression in astrocytomas recapitulates that of progenitor cells during neurodevelopment, and suggests a role for Numb in astrocytoma oncogenesis.

Dual role of autophagy in hallmarks of cancer.

Evolutionarily conserved across eukaryotic cells, macroautophagy (herein autophagy) is an intracellular catabolic degradative process targeting damaged and superfluous cellular proteins, organelles, and other cytoplasmic components. Mechanistically, it involves formation of double-membrane vesicles called autophagosomes that capture cytosolic cargo and deliver it to lysosomes, wherein the breakdown products are eventually recycled back to the cytoplasm. Dysregulation of autophagy often results in various disease manifestations, including neurodegeneration, microbial infections, and cancer. In the case of cancer, extensive attention has been devoted to understanding the paradoxical roles of autophagy in tumor suppression and tumor promotion. In this review, while we summarize how this self-eating process is implicated at various stages of tumorigenesis, most importantly, we address the link between autophagy and hallmarks of cancer. This would eventually provide a better understanding of tumor dependence on autophagy. We also discuss how therapeutics targeting autophagy can counter various transformations involved in tumorigenesis. Finally, this review will provide a novel insight into the mutational landscapes of autophagy-related genes in several human cancers, using genetic information collected from an array of cancers.

Author Correction: PTEN-L is a novel protein phosphatase for ubiquitin dephosphorylation to inhibit PINK1-Parkin-mediated mitophagy.

We apologize for three errors that we just found in the paper published online on 22 June 2018.

PTEN-L is a novel protein phosphatase for ubiquitin dephosphorylation to inhibit PINK1-Parkin-mediated mitophagy.

Mitophagy is an important type of selective autophagy for specific elimination of damaged mitochondria. PTEN-induced putative kinase protein 1 (PINK1)-catalyzed phosphorylation of ubiquitin (Ub) plays a critical role in the onset of PINK1-Parkin-mediated mitophagy. Phosphatase and tensin homolog (PTEN)-long (PTEN-L) is a newly identified isoform of PTEN, with addition of 173 amino acids to its N-terminus. Here we report that PTEN-L is a novel negative regulator of mitophagy via its protein phosphatase activity against phosphorylated ubiquitin. We found that PTEN-L localizes at the outer mitochondrial membrane (OMM) and overexpression of PTEN-L inhibits, whereas deletion of PTEN-L promotes, mitophagy induced by various mitochondria-damaging agents. Mechanistically, PTEN-L is capable of effectively preventing Parkin mitochondrial translocation, reducing Parkin phosphorylation, maintaining its closed inactive conformation, and inhibiting its E3 ligase activity. More importantly, PTEN-L reduces the level of phosphorylated ubiquitin (pSer65-Ub) in vivo, and in vitro phosphatase assay confirms that PTEN-L dephosphorylates pSer65-Ub via its protein phosphatase activity, independently of its lipid phosphatase function. Taken together, our findings demonstrate a novel function of PTEN-L as a protein phosphatase for ubiquitin, which counteracts PINK1-mediated ubiquitin phosphorylation leading to blockage of the feedforward mechanisms in mitophagy induction and eventual suppression of mitophagy. Thus, understanding this novel function of PTEN-L provides a key missing piece in the molecular puzzle controlling mitophagy, a critical process in many important human diseases including neurodegenerative disorders such as Parkinson's disease.

Breast Cancer: Exploring the Facts and Holistic Needs during and beyond Treatment.

Breast cancer patients face challenges throughout the journey of diagnosis, treatment, post-treatment, and recovery. The breast cancer patient is exposed to a multidisciplinary team including doctors, nurses, therapists, counselors, and psychologists. While the team assembled together aims to address multiple facets in breast cancer care, the sub-specialized nature of individual professional practices may constrain the overview of patients' holistic needs and a comprehensive approach to cancer management. This paper aims to provide an overview of the holistic needs of breast cancer patients at each stage of their cancer journey, addressing their complex physical, psychological, and social needs. As every patient is different, cancer care has to be tailored to each patient based on a holistic needs assessment. This paper also explores how support can be provided from the perspectives of the healthcare providers, family members and caretakers. Examples of general practices at healthcare institutions worldwide as well as supportive care provided by support groups are discussed. The needs of breast cancer patients extend beyond the resolution of cancer as a disease, and the restoration of health as far as possible is a critical component of healing. Understanding the complex issues involved in the journey of breast cancer will aid healthcare providers to be better equipped to sensitively address their concerns and focus on healing the patient holistically. METHODOLOGY: This paper provides a literature review of validated practices in different countries and elaborates on the holistic needs of patients at various stages of recovery. This review is based on more than a decade of publications sourced from multiple resources including PubMed journal articles; books and official websites of breast cancer organizations.

'Lnc'-ing Wnt in female reproductive cancers: therapeutic potential of long non-coding RNAs in Wnt signalling.

Recent discoveries in the non-coding genome have challenged the original central dogma of molecular biology, as non-coding RNAs and related processes have been found to be important in regulating gene expression. MicroRNAs and long non-coding RNAs (lncRNAs) are among those that have gained attention recently in human diseases, including cancer, with the involvement of many more non-coding RNAs (ncRNAs) waiting to be discovered. ncRNAs are a group of ribonucleic acids transcribed from regions of the human genome, which do not become translated into proteins, despite having essential roles in cellular physiology. Deregulation of ncRNA expression and function has been observed in cancer pathogenesis. Recently, the roles of a group of ncRNA known as lncRNA have gained attention in cancer, with increasing reports of their oncogenic involvement. Female reproductive cancers remain a leading cause of death in the female population, accounting for almost a third of all female cancer deaths in 2016. The Wnt signalling pathway is one of the most important oncogenic signalling pathways which is hyperactivated in cancers, including female reproductive cancers. The extension of ncRNA research into their mechanistic roles in human cancers has also led to novel reported roles of ncRNAs in the Wnt pathway and Wnt-mediated oncogenesis. This review aims to provide a critical summary of the respective roles and cellular functions of Wnt-associated lncRNAs in female reproductive cancers and explores the potential of circulating cell-free lncRNAs as diagnostic markers and lncRNAs as therapeutic targets. LINKED ARTICLES: This article is part of a themed section on WNT Signalling: Mechanisms and Therapeutic Opportunities. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.24/issuetoc.

Wanted DEAD/H or Alive: Helicases Winding Up in Cancers.

Cancer is one of the most studied areas of human biology over the past century. Despite having attracted much attention, hype, and investments, the search to find a cure for cancer remains an uphill battle. Recent discoveries that challenged the central dogma of molecular biology not only further increase the complexity but also demonstrate how various types of noncoding RNAs such as microRNA and long noncoding RNA, as well as their related processes such as RNA editing, are important in regulating gene expression. Parallel to this aspect, an increasing number of reports have focused on a family of proteins known as DEAD/H-box helicases involved in RNA metabolism, regulation of long and short noncoding RNAs, and novel roles as "editing helicases" and their association with cancers. This review summarizes recent findings on the roles of RNA helicases in various cancers, which are broadly classified into adult solid tumors, childhood solid tumors, leukemia, and cancer stem cells. The potential small molecule inhibitors of helicases and their therapeutic value are also discussed. In addition, analyzing next-generation sequencing data obtained from public portals and reviewing existing literature, we provide new insights on the potential of DEAD/H-box helicases to act as pharmacological drug targets in cancers.