MyMedR

Displaying all 6 publications

Abstract:

Sort:

Liquid biopsy in breast carcinoma: Are we there yet?

Wijesinghe HD, Lokuhetty MDS

Malays J Pathol, 2023 Aug;45(2):175-186.
PMID: 37658527

Breast carcinoma is the most common malignancy among women worldwide. Liquid biopsy is a method of obtaining tumour-derived material from blood and body fluid. This includes the assessment of circulating tumour cells (CTCs), circulating tumour deoxyribose nucleic acid (ctDNA), tumour educated platelets (TEPs) and exosomes. Detection of CTCs and ctDNA in liquid biopsy has been shown to have prognostic and predictive value in both early and metastatic breast carcinoma. The study of CTCs could also advance our understanding of aspects of tumour biology, including epithelial mesenchymal transition. ctDNA can be used to assess and monitor the molecular profile of breast carcinoma. It may help detect new genetic alterations in tumours and predict disease progression before the onset of clinical features or radiological evidence. TEPs and exosomes are also emerging as diagnostic, prognostic and predictive markers of breast carcinoma. Thus, liquid biopsy provides a non-invasive, repeatable method for the dynamic assessment of the tumour. Many methods have been used for the detection of CTCs and ctDNA. Most of these are still in the research stage and only the CellSearch method for the detection of CTCs and Therascreen PIK3CA RGQ polymerase chain reaction (PCR) assay for the detection of PIK3CA (Phosphatidylinositol-4,5-Bisphosphate 3-Kinase Catalytic Subunit Alpha) mutations in liquid biopsy have approval of the United States, Food and Drug Administration. However, their high costs, lack of standardized procedures, and a long and complicated detection process have limited their use. Despite its limitations, liquid biopsy is a useful tool in clinical decision making and has the potential to play an increasingly important role in the management of breast carcinoma in the future as we move toward more personalized cancer care.

Matched MeSH terms: Class I Phosphatidylinositol 3-Kinases
Network pharmacology-integrated molecular docking analysis of phytocompounds of Caesalpinia pulcherrima (peacock flower) as potential anti-metastatic agents

Hao Dong T, Yau Wen Ning A, Yin Quan T

J Biomol Struct Dyn, 2024;42(4):1778-1794.
PMID: 37060321 DOI: 10.1080/07391102.2023.2202273

Caesalpinia pulcherrima, or peacock flower, has been a subject of cancer therapeutics research, showing promising anti-cancer and anti-metastatic properties. The present research aims to investigate the anti-metastatic potential of the flower, through bioinformatics approaches. Metastasis targets numbering 471 were identified through overlap analysis following NCBI gene, Gene Card and OMIM query. Phytocompounds of the flower were retrieved from PubChem and their protein interactions predicted using Super-PRED and TargetNet. The 28 targets that overlapped with the predicted proteins were used to generate STRING >0.7. Enrichment analysis revealed that C. pulcherrima may inhibit metastasis through angiogenesis-related and leukocyte migration-related pathways. HSP90AA1, ESR1, PIK3CA, ERBB2, KDR and MMP9 were identified as potential core targets while and 6 compounds (3-[(4-Hydroxyphenyl)methylidene]-7,8-dimethoxychromen-4-one (163076213), clotrimazole (2812), Isovouacapenol A (636673), [(4aR,5R,6aS,7R,11aS,11bR)-4a-hydroxy-4,4,7,11b-tetramethyl-9-oxo-1,2,3,5,6,6a,7,11a-octahydronaphtho[2,1-f][1]benzofuran-5-yl] benzoate (163104827), Stigmast-5-en-3beta-ol (86821) and 4,2'-dihydroxy-4'-methoxychalcone (592216)) were identified as potential core compounds. Molecular docking analysis and molecular dynamics simulations investigations revealed that ERBB2, HSP90AA1 and KDR, along with the newly discovered 163076213 compound to be the most significant metastasis targets and bioactive compound, respectively. These three core targets demonstrated interactions consistent with angiogenesis and leukocyte migration pathways. Furthermore, potentially novel interactions, such as KDR-MMP9, KDR-PIK3CA, ERBB2-HSP90AA1, ERBB2-ESR1, ERBB2-PIK3CA and ERBB2-MMP9 interactions were identified and may play a role in crosslinking the aforementioned metastatic pathways. Therefore, the present study revealed the main mechanisms behind the anti-metastatic effects of C. pulcherrima, paving the path for further research on these compounds and proteins to accelerate the research of cancer therapeutics and application of C. pulcherrima.Communicated by Ramaswamy H. Sarma.

Matched MeSH terms: Class I Phosphatidylinositol 3-Kinases
Phosphoinositide 3-kinase δ inactivation prevents vitreous-induced activation of AKT/MDM2/p53 and migration of retinal pigment epithelial cells

Han H, Chen N, Huang X, Liu B, Tian J, Lei H

J Biol Chem, 2019 10 18;294(42):15408-15417.
PMID: 31467081 DOI: 10.1074/jbc.RA119.010130

Phosphoinositide 3-kinases (PI3Ks) are a family of lipid kinases that play a critical role in transmitting signals from cell-surface molecules to intracellular protein effectors. Key PI3Ks include PI3Kα, PI3Kβ, and PI3Kδ, which are regulated by receptors. The signaling pathway comprising the PI3Ks, along with a Ser/Thr kinase (AKT), a proto-oncogene product (mouse double minute (MDM)2), and a tumor suppressor protein (p53), plays an essential role in experimental proliferative vitreoretinopathy (PVR), which is a fibrotic blinding eye disorder. However, which PI3K isoforms are involved in PVR is unknown. A major characteristic of PVR is the formation of epi (or sub)-retinal membranes that consist of extracellular matrix and cells, including retinal pigment epithelium (RPE) cells, glial cells, and macrophages. RPE cells are considered key players in PVR pathogenesis. Using immunoblotting and immunofluorescence analyses, we herein provide the evidence that PI3Kδ is highly expressed in human RPEs when it is primarily expressed in leukocytes. We also found that PI3Kδ inactivation through two approaches, CRISPR/Cas9-mediated depletion and a PI3Kδ-specific inhibitor (idelalisib), not only blocks vitreous-induced activation of AKT and MDM2 but also abrogates a vitreous-stimulated decrease in p53. Furthermore, we demonstrate that PI3Kδ inactivation prevents vitreous-induced proliferation, migration, and contraction of human RPEs. These results suggest that PI3Kδ may represent a potential therapeutic target for RPE-related eye diseases, including PVR.

Matched MeSH terms: Class I Phosphatidylinositol 3-Kinases/genetics; Class I Phosphatidylinositol 3-Kinases/metabolism*
Phenotypic and molecular dissection of metaplastic breast cancer and the prognostic implications

McCart Reed AE, Kalaw E, Nones K, Bettington M, Lim M, Bennett J, et al.

J Pathol, 2019 02;247(2):214-227.
PMID: 30350370 DOI: 10.1002/path.5184

Metaplastic breast carcinoma (MBC) is relatively rare but accounts for a significant proportion of global breast cancer mortality. This group is extremely heterogeneous and by definition exhibits metaplastic change to squamous and/or mesenchymal elements, including spindle, squamous, chondroid, osseous, and rhabdomyoid features. Clinically, patients are more likely to present with large primary tumours (higher stage), distant metastases, and overall, have shorter 5-year survival compared to invasive carcinomas of no special type. The current World Health Organisation (WHO) diagnostic classification for this cancer type is based purely on morphology - the biological basis and clinical relevance of its seven sub-categories are currently unclear. By establishing the Asia-Pacific MBC (AP-MBC) Consortium, we amassed a large series of MBCs (n = 347) and analysed the mutation profile of a subset, expression of 14 breast cancer biomarkers, and clinicopathological correlates, contextualising our findings within the WHO guidelines. The most significant indicators of poor prognosis were large tumour size (T3; p = 0.004), loss of cytokeratin expression (lack of staining with pan-cytokeratin AE1/3 antibody; p = 0.007), EGFR overexpression (p = 0.01), and for 'mixed' MBC, the presence of more than three distinct morphological entities (p = 0.007). Conversely, fewer morphological components and EGFR negativity were favourable indicators. Exome sequencing of 30 cases confirmed enrichment of TP53 and PTEN mutations, and intriguingly, concurrent mutations of TP53, PTEN, and PIK3CA. Mutations in neurofibromatosis-1 (NF1) were also overrepresented [16.7% MBCs compared to ∼5% of breast cancers overall; enrichment p = 0.028; mutation significance p = 0.006 (OncodriveFM)], consistent with published case reports implicating germline NF1 mutations in MBC risk. Taken together, we propose a practically minor but clinically significant modification to the guidelines: all WHO_1 mixed-type tumours should have the number of morphologies present recorded, as a mechanism for refining prognosis, and that EGFR and pan-cytokeratin expression are important prognostic markers. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Matched MeSH terms: Class I Phosphatidylinositol 3-Kinases/genetics
Fulltext Perturbation of PI3K/Akt signaling affected autophagy modulation in dystrophin-deficient myoblasts

Yazid MD, Hung-Chih C

Cell Commun Signal, 2021 10 27;19(1):105.
PMID: 34706731 DOI: 10.1186/s12964-021-00785-0

BACKGROUND: The absence of dystrophin has gave a massive impact on myotube development in Muscular Dystrophy pathogenesis. One of the conserved signaling pathways involved in skeletal muscle differentiation is the PI3K/Akt/mTOR pathway that plays a vital role in autophagy regulation. To further understand and establish targeted therapy in dystrophin-deficient myoblasts, protein expression profiling has been determined which provides information on perturbed autophagy modulation and activation.
METHODS: In this study, a dystrophin-deficient myoblast cell line established from the skeletal muscle of a dystrophic (mdx) mouse was used as a model. The dfd13 (dystrophin-deficient) and C2C12 (non-dystrophic) myoblasts were cultured in low mitogen conditions for 10 days to induce differentiation. The cells were subjected to total protein extraction prior to Western blotting assay technique. Protein sub-fractionation has been conducted to determine protein localization. The live-cell analysis of autophagy assay was done using a flow cytometer.
RESULTS: In our culture system, the dfd13 myoblasts did not achieve terminal differentiation. PTEN expression was profoundly increased in dfd13 myoblasts throughout the differentiation day subsequently indicates perturbation of PI3K/Akt/mTOR regulation. In addition, rictor-mTORC2 was also found inactivated in this event. This occurrence has caused FoxO3 misregulation leads to higher activation of autophagy-related genes in dfd13 myoblasts. Autophagosome formation was increased as LC3B-I/II showed accumulation upon differentiation. However, the ratio of LC3B lipidation and autophagic flux were shown decreased which exhibited dystrophic features.
CONCLUSION: Perturbation of the PTEN-PI3K/Akt pathway triggers excessive autophagosome formation and subsequently reduced autophagic flux within dystrophin-deficient myoblasts where these findings are of importance to understand Duchenne Muscular Dystrophy (DMD) patients. We believe that some manipulation within its regulatory signaling reported in this study could help restore muscle homeostasis and attenuate disease progression. Video Abstract.

Matched MeSH terms: Class I Phosphatidylinositol 3-Kinases/genetics
Fulltext Common oncogenic mutations are infrequent in oral squamous cell carcinoma of Asian origin

Zanaruddin SN, Yee PS, Hor SY, Kong YH, Ghani WM, Mustafa WM, et al.

PLoS One, 2013;8(11):e80229.
PMID: 24224046 DOI: 10.1371/journal.pone.0080229

OBJECTIVES: The frequency of common oncogenic mutations and TP53 was determined in Asian oral squamous cell carcinoma (OSCC).
MATERIALS AND METHODS: The OncoCarta(™) panel v1.0 assay was used to characterize oncogenic mutations. In addition, exons 4-11 of the TP53 gene were sequenced. Statistical analyses were conducted to identify associations between mutations and selected clinico-pathological characteristics and risk habits.
RESULTS: Oncogenic mutations were detected in PIK3CA (5.7%) and HRAS (2.4%). Mutations in TP53 were observed in 27.7% (31/112) of the OSCC specimens. Oncogenic mutations were found more frequently in non-smokers (p = 0.049) and TP53 truncating mutations were more common in patients with no risk habits (p = 0.019). Patients with mutations had worse overall survival compared to those with absence of mutations; and patients who harbored DNA binding domain (DBD) and L2/L3/LSH mutations showed a worse survival probability compared to those patients with wild type TP53. The majority of the oncogenic and TP53 mutations were G:C > A:T and A:T > G:C base transitions, regardless of the different risk habits.
CONCLUSION: Hotspot oncogenic mutations which are frequently present in common solid tumors are exceedingly rare in OSCC. Despite differences in risk habit exposure, the mutation frequency of PIK3CA and HRAS in Asian OSCC were similar to that reported in OSCC among Caucasians, whereas TP53 mutations rates were significantly lower. The lack of actionable hotspot mutations argue strongly for the need to comprehensively characterize gene mutations associated with OSCC for the development of new diagnostic and therapeutic tools.

Matched MeSH terms: Class I Phosphatidylinositol 3-Kinases