The application of Raman spectroscopy for the diagnosis and monitoring of lung tumors.

Raman spectroscopy is an optical technique that uses inelastic light scattering in response to vibrating molecules to produce chemical fingerprints of tissues, cells, and biofluids. Raman spectroscopy strategies produce high levels of chemical specificity without requiring extensive sample preparation, allowing for the use of advanced optical tools such as microscopes, fiber optics, and lasers that operate in the visible and near-infrared spectral range, making them increasingly suitable for a wide range of medical diagnostic applications. Metal nanoparticles and nonlinear optical effects can improve Raman signals, and optimized fiber optic Raman probes can make real-time, in vivo, single-point observations. Furthermore, diagnostic speed and spatial accuracy can be improved through the multimodal integration of Raman measurements and other technologies. Recent studies have significantly contributed to the improvement of diagnostic speed and accuracy, making them suitable for clinical application. Lung cancer is a prevalent type of respiratory malignancy. However, the use of computed tomography for detection and screening frequently reveals numerous smaller lung nodules, which makes the diagnostic process more challenging from a clinical perspective. While the majority of small nodules detected are benign, there are currently no direct methods for identifying which nodules represent very early-stage lung cancer. Positron emission tomography and other auxiliary diagnostic methods for non-surgical biopsy samples from these small nodules yield low detection rates, which might result in significant expenses and the possibility of complications for patients. While certain subsets of patients can undergo curative treatment, other individuals have a less favorable prognosis and need alternative therapeutic interventions. With the emergence of new methods for treating cancer, such as immunotherapies, which can potentially extend patient survival and even lead to a complete cure in certain instances, it is crucial to determine the most suitable biomarkers and metrics for assessing the effectiveness of these novel compounds. This will ensure that significant treatment outcomes are accurately measured. This review provides a comprehensive overview of the prospects of Raman spectroscopy and its applications in the diagnosis and analysis of lung tumors.

Key candidate genes and pathways in T lymphoblastic leukemia/lymphoma identified by bioinformatics and serological analyses.

T-cell acute lymphoblastic leukemia (T-ALL)/T-cell lymphoblastic lymphoma (T-LBL) is an uncommon but highly aggressive hematological malignancy. It has high recurrence and mortality rates and is challenging to treat. This study conducted bioinformatics analyses, compared genetic expression profiles of healthy controls with patients having T-ALL/T-LBL, and verified the results through serological indicators. Data were acquired from the GSE48558 dataset from Gene Expression Omnibus (GEO). T-ALL patients and normal T cells-related differentially expressed genes (DEGs) were investigated using the online analysis tool GEO2R in GEO, identifying 78 upregulated and 130 downregulated genes. Gene Ontology (GO) and protein-protein interaction (PPI) network analyses of the top 10 DEGs showed enrichment in pathways linked to abnormal mitotic cell cycles, chromosomal instability, dysfunction of inflammatory mediators, and functional defects in T-cells, natural killer (NK) cells, and immune checkpoints. The DEGs were then validated by examining blood indices in samples obtained from patients, comparing the T-ALL/T-LBL group with the control group. Significant differences were observed in the levels of various blood components between T-ALL and T-LBL patients. These components include neutrophils, lymphocyte percentage, hemoglobin (HGB), total protein, globulin, erythropoietin (EPO) levels, thrombin time (TT), D-dimer (DD), and C-reactive protein (CRP). Additionally, there were significant differences in peripheral blood leukocyte count, absolute lymphocyte count, creatinine, cholesterol, low-density lipoprotein, folate, and thrombin times. The genes and pathways associated with T-LBL/T-ALL were identified, and peripheral blood HGB, EPO, TT, DD, and CRP were key molecular markers. This will assist the diagnosis of T-ALL/T-LBL, with applications for differential diagnosis, treatment, and prognosis.

Bioinformatics and Raman spectroscopy-based identification of key pathways and genes enabling differentiation between acute myeloid leukemia and T cell acute lymphoblastic leukemia.

Acute myeloid leukemia (AML) and T cell acute lymphoblastic leukemia (T-ALL) are two of the most prevalent hematological malignancies diagnosed among adult leukemia patients, with both being difficult to treat and associated with high rates of recurrence and mortality. In the present study, bioinformatics approaches were used to analyze both of these types of leukemia in an effort to identify characteristic gene expression patterns that were subsequently validated via Raman spectroscopy. For these analyses, four Gene Expression Omnibus datasets (GSE13204, GSE51082, GSE89565, and GSE131184) pertaining to acute leukemia were downloaded, and differentially expressed genes (DEGs) were then identified through comparisons of AML and T-ALL patient samples using the R Bioconductor package. Shared DEGs were then subjected to Gene Ontology (GO) enrichment analyses and were used to establish a protein-protein interaction (PPI) network analysis. In total, 43 and 129 upregulated and downregulated DEGs were respectively identified. Enrichment analyses indicated that these DEGs were closely tied to immune function, collagen synthesis and decomposition, inflammation, the synthesis and decomposition of lipopolysaccharide, and antigen presentation. PPI network module clustering analyses further led to the identification of the top 10 significantly upregulated and downregulated genes associated with disease incidence. These key genes were then validated in patient samples via Raman spectroscopy, ultimately confirming the value of these genes as tools that may aid the differential diagnosis and treatment of AML and T-ALL. Overall, these results thus highlight a range of novel pathways and genes that are linked to the incidence and progression of AML and T-ALL, providing a list of important diagnostic and prognostic molecular markers that have the potential to aid in the clinical diagnosis and treatment of these devastating malignancies.

Application of serum Raman spectroscopy in rapid and early discrimination of aplastic anemia and myelodysplastic syndrome.

BACKGROUND: Raman spectroscopy of hematological diseases has gained attention from various researchers. However, serum analysis of bone marrow failure (BMF), represented by aplastic anemia (AA) and myelodysplastic syndromes (MDS) has not been fully investigated. In this study, we aimed at establishing a simple, non-invasive serum detection method for AA and MDS. METHOD: Serum samples from 35 AA patients (N = 35), MDS patients (N = 25), and control volunteers (N = 23) were systematically analyzed via laser Raman spectroscopy, and orthogonal partial least squares discrimination analysis (OPLS-DA). Then, discrimination models between the BMFs and control were constructed and evaluated using the prediction set. RESULTS: Compared to control volunteers, serum spectral data for BMF patients were specific. The intensities of Raman peaks representing nucleic acids (726, 781, 786, 1078, 1190, 1415 cm-1), proteins (1221 cm-1), phospholipid/cholesterol (1285 cm-1), and ß-carotene (1162 cm-1) significantly decreased, while the intensity of lipids (1437 and 1446 cm-1) significantly increased. Intensities of Raman peaks representing nucleic acids (726 cm-1) and collagen (1344 cm-1) in the AA group were significantly lower than in the control group. Intensities of Raman peaks representing nucleic acids (726 and 786 cm-1), proteins (1003 cm-1), and collagen (1344 cm-1) in the MDS group were significantly lower than those of the control group. The intensity of Raman peaks representing lipids (1437 and 1443 cm-1) in the MDS group was significantly higher than in the control group. Patients with AA and MDS exhibited increased serum triglyceride levels and decreased high-density lipoprotein levels. CONCLUSIONS: The relationship between serological test data for patients and typing of AA and MDS provides essential information for rapid and early identification of BMF. This study shows the potential of Raman spectroscopy for non-invasive detection of different BMF types.

Elucidating the cell metabolic heterogeneity during hematopoietic lineage differentiation based on Met-Flow.

Cell metabolism is critically involved in the differentiation of the hematopoietic lineage and, therefore, has attracted the attention of researchers, however, in-depth studies on cellular metabolic activity of hematopoietic cells (HCs) require attention. This investigation compared the metabolic activity of HCs at critical lineage differentiation stages, including hematopoietic stem cells (HSCs), hematopoietic progenitor cells (HPCs), and differentiated blood cells, via multiple methods and basic reference values. Primary metabolic processes of HCs, including anabolism, catabolism, phosphate, and glucose metabolism, were analyzed, and their maps were drawn. The data revealed that GLUT1 expression in HSCs was substantially higher than in all progenitor cells and mature myeloid blood cells, indicating their strong glucose uptake capacity. In myeloid differentiation, the ACAC expression of HPC2 was markedly higher than in neutrophils and monocytes. The ACAC, ASS1, ATP5A, and PRDX2 of HPC2 expression in lymphoid differentiation was substantially greater than in B and Natural-killer cells. CLP, CMP, GMP, MEP, and HPC1 inherit increased glucose uptake stem cell properties. In lymphocyte subsets, the expression of ACAC, ASS1, ATP5A, CPT1A, and PRDX2 in CD4+ T subgroups (naive and memory CD4+ T and nTreg) were elevated than in B subgroups (pro-, pre-, immature and mature Bs) and CD8+ T subgroups. Furthermore, leukemia stem cells (LSCs) had increased levels of ACAC, CPT1A, G6PD, IDH2, and PRDX2 than leukemia cells, indicating a stronger metabolic capacity of LSCs than differentiated leukemia cells.

Elucidating the Heterogeneity of Serum Metabolism in Patients with Myelodysplastic Syndrome and Acute Myeloid Leukemia by Raman Spectroscopy.

Myelodysplastic syndrome (MDS) is difficult to diagnose and classify because it has the potential to evolve into acute myeloid leukemia (AML). Raman spectroscopy and orthogonal partial least squares discrimination analysis (OPLS-DA) are used to systematically analyze peripheral blood serum samples from 33 patients with MDS, 25 patients with AML, and 29 control volunteers to gain insight into the heterogeneity of serum metabolism in patients with MDS and AML. AML patients show unique serum spectral data compared to MDS patients with considerably greater peak intensities of collagen (859 and 1345 cm-1) and carbohydrate (920 and 1123 cm-1) compared to MDS patients. Screening and bioinformatics analysis of MDS- and AML-related genes based on the Gene Expression Omnibus (GEO) database shows that 1459 genes are differentially expressed, and the main signaling pathways are related to Th17 cell differentiation, pertussis, and cytokine receptor interaction. Statistical analysis of serological indexes related to glucose and lipid metabolism shows that patients with AML have increased serum triglyceride (TG) levels and decreased total protein levels. This study provides a spectral basis for the relationship between the massive serological data of patients and the typing of MDS and AML and provides important information for the rapid and early identification of MDS and AML.

Elucidating the mitochondrial function of murine lymphocyte subsets and the heterogeneity of the mitophagy pathway inherited from hematopoietic stem cells.

Background: Mitochondria are mainly involved in ATP production to meet the energy demands of cells. Researchers are increasingly recognizing the important role of mitochondria in the differentiation and activation of hematopoietic cells, but research on how mitochondrial metabolism influence different subsets of lymphocyte at different stages of differentiation and activation are yet to be carried out. In this work, the mitochondrial functions of lymphocytes were compared at different differentiation and activation stages and included CD8+ T lymphocytes, CD4+ T lymphocytes, B lymphocytes, NK cells as well as their subsets. For this purpose, a complete set of methods was used to comprehensively analyze mitophagy levels, mitochondrial reactive oxygen species (ROS), mitochondrial membrane potential (MMP) and the mitochondrial mass (MM) of subsets of lymphocytes. It is expected that this will provide a complete set of standards, and drawing the mitochondrial metabolic map of lymphocyte subsets at different stages of differentiation and activation. Results and discussion: Of all lymphocytes, B cells had a relatively high mitochondrial metabolic activity which was evident from the higher levels of mitophagy, ROS, MMP and MM, and this reflected the highly heterogeneous nature of the mitochondrial metabolism in lymphocytes. Among the B cell subsets, pro-B cells had relatively higher levels of MM and MMP, while the mitochondrial metabolism level of mature B cells was relatively low. Similarly, among the subsets of CD4+ T cell, a relatively higher level of mitochondrial metabolism was noted for naive CD4+ T cells. Finally, from the CD8+ T cell subsets, CD8+ Tcm had relatively high levels of MM and MMP but relatively low ones for mitophagy, with effector T cells displaying the opposite characteristics. Meanwhile, the autophagy-related genes of lymphoid hematopoietic cells including hematopoietic stem cells, hematopoietic progenitor cells and lymphocyte subsets were analyzed, which preliminarily showed that these cells were heterogeneous in the selection of mitophagy related Pink1/Park2, BNIP3/NIX and FUNDC1 pathways. The results showed that compared with CD4+ T, CD8+ T and NK cells, B cells were more similar to long-term hematopoietic stem cell (LT-HSC) and short-term hematopoietic stem cell (ST-HSC) in terms of their participation in the Pink1/Park2 pathway, as well as the degree to which the characteristics of autophagy pathway were inherited from HSC. Compared with CLP and B cells, HSC are less involved in BNIP3/NIX pathway. Among the B cell subsets, pro-B cells inherited the least characteristics of HSC in participating in Pink1/Park2 pathway compared with pre-B, immature B and immature B cells. Among CD4+ T cell subsets, nTreg cells inherited the least characteristics of HSC in participating in Pink1/Park2 pathway compared with naive CD4+ T and memory CD4+ T cells. Among the CD8+ T cell subsets, compared with CLP and effector CD8+ T cells, CD8+ Tcm inherit the least characteristics of HSC in participating in Pink1/Park2 pathway. Meanwhile, CLP, naive CD4+ T and effector CD8+ T were more involved in BNIP3/NIX pathway than other lymphoid hematopoietic cells. Conclusion: This study is expected to provide a complete set of methods and basic reference values for future studies on the mitochondrial functions of lymphocyte subsets at different stages of differentiation and activation in physiological state, and also provides a standard and reference for the study of infection and immunity based on mitochondrial metabolism.

Mesenchymal stromal cell treatment attenuates repetitive mild traumatic brain injury-induced persistent cognitive deficits via suppressing ferroptosis.

The incidence of repetitive mild traumatic brain injury (rmTBI), one of the main risk factors for predicting neurodegenerative disorders, is increasing; however, its underlying mechanism remains unclear. As suggested by several studies, ferroptosis is possibly related to TBI pathophysiology, but its effect on rmTBI is rarely studied. Mesenchymal stromal cells (MSCs), the most studied experimental cells in stem cell therapy, exert many beneficial effects on diseases of the central nervous system, yet evidence regarding the role of MSCs in ferroptosis and post-rmTBI neurodegeneration is unavailable. Our study showed that rmTBI resulted in time-dependent alterations in ferroptosis-related biomarker levels, such as abnormal iron metabolism, glutathione peroxidase (GPx) inactivation, decrease in GPx4 levels, and increase in lipid peroxidation. Furthermore, MSC treatment markedly decreased the aforementioned rmTBI-mediated alterations, neuronal damage, pathological protein deposition, and improved cognitive function compared with vehicle control. Similarly, liproxstatin-1, a ferroptosis inhibitor, showed similar effects. Collectively, based on the above observations, MSCs ameliorate cognitive impairment following rmTBI, partially via suppressing ferroptosis, which could be a therapeutic target for rmTBI.

Rapid and non-invasive discrimination of acute leukemia bone marrow supernatants by Raman spectroscopy and multivariate statistical analysis.

A simple and non-invasive detection method for acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) was established by systematically investigating the characteristics of bone marrow supernatants from 61 AML patients, 22 ALL patients, and 5 volunteers without hematological tumors by Raman spectroscopy and orthogonal partial least squares discriminant analysis (OPLS-DA). The control group could be well distinguished from the AML and ALL groups by Raman peaks of 859, 1031, 1437, 1443, 1446, 1579, and 1603 cm-1 and from the AML subtypes groups (AML-M2, AML-M3, AML-M4, and AML-M5) by the Raman peaks of 859, 1221, 1230, 1437, 1443, and 1603 cm-1, indicating high sensitivity and specificity of the method. Potentially important variables of acute leukemia (AL) prognosis, such as cholesterol, high-density lipoprotein, low-density lipoprotein, adenosine deaminase, and hemoglobin, could be effectively identified by Raman peaks of 1437, 1443, and 1579 cm-1. Therefore, Raman spectroscopy can be considered as a new non-invasive clinical tool for the detection of different types of AL and can be used to correlate biochemical parameters of AL patients with the classification and prognosis of AL.

Neuron-derived exosomes with high miR-21-5p expression promoted polarization of M1 microglia in culture.

BACKGROUND: Neuroinflammation is a characteristic pathological change of acute neurological deficit and chronic traumatic encephalopathy (CTE) after traumatic brain injury (TBI). Microglia are the key cell involved in neuroinflammation and neuronal injury. The type of microglia polarization determines the direction of neuroinflammation. MiR-21-5p elevated in neurons and microglia after TBI in our previous research. In this study, we explore the influence of miR-21-5p for neuroinflammation by regulating microglia polarization. METHODS: In this study, PC12 and BV2 used to instead of neuron and microglia respectively. The co-cultured transwell system used to simulate interaction of PC12 and BV2 cells in vivo environment. RESULTS: We found that PC12-derived exosomes with containing miR-21-5p were phagocytosed by microglia and induced microglia polarization, meanwhile, the expression of miR-21-5p was increased in M1 microglia cells. Polarization of M1 microglia aggravated the release of neuroinflammation factors, inhibited the neurite outgrowth, increased accumulation of P-tau and promoted the apoptosis of PC12 cells, which formed a model of cyclic cumulative damage. Simultaneously, we also got similar results in vivo experiments. CONCLUSIONS: PC12-derived exosomes with containing miR-21-5p is the essential of this cyclic cumulative damage model. Therefore, regulating the expression of miR-21-5p or the secretion of exosomes may be an important novel strategy for the treatment of neuroinflammation after TBI.

Transplantation of in vitro cultured endothelial progenitor cells repairs the blood-brain barrier and improves cognitive function of APP/PS1 transgenic AD mice.

To date, the pathogenesis of Alzheimer's disease (AD) remains unclear. It is well-known that excessive deposition of Aß in the brain is a crucial part of the pathogenesis of AD. In recent years, the AD neurovascular unit hypothesis has attracted much attention. Impairment of the blood-brain barrier (BBB) leads to abnormal amyloid-ß (Aß) transport, and chronic cerebral hypoperfusion causes Aß deposition throughout the onset and progression of AD. Endothelial progenitor cells (EPCs) are the universal cells for repairing blood vessels. Our previous studies have shown that a reduced number of EPCs in the peripheral blood results in cerebral vascular repair disorder, cerebral hypoperfusion and neurodegeneration, which might be related to the cognitive dysfunction of AD patients. This study was designed to confirm whether EPCs transplantation could repair the blood-brain barrier, stimulate angiogenesis and reduce Aß deposition in AD. The expression of ZO-1, Occludin and Claudin-5 was up-regulated in APP/PS1 transgenic mice after hippocampal transplantation of EPCs. Consistent with previous studies, EPC transplants also increased the microvessel density. We observed that Aß senile plaque deposition was decreased and hippocampal cell apoptosis was reduced after EPCs transplantation. The Morris water maze test showed that spatial learning and memory functions were significantly improved in mice transplanted with EPCs. Consequently, EPCs could up-regulate the expression of tight junction proteins, repair BBB tight junction function, stimulate angiogenesis, promote Aß clearance, and decrease neuronal loss, ultimately improve cognitive function. Taken together, these data demonstrate EPCs may play an important role in the therapeutic implications for vascular dysfunction in AD.

Concerted activities of distinct H4K20 methyltransferases at DNA double-strand breaks regulate 53BP1 nucleation and NHEJ-directed repair.

Although selective binding of 53BP1 to dimethylated histone H4 lysine 20 (H4K20me2) at DNA double-strand breaks (DSBs) is a necessary and pivotal determinant of nonhomologous end joining (NHEJ)-directed repair, the enzymes that generate H4K20me2 at DSBs were unclear. Here, we determined that the PR-Set7 monomethyltransferase (H4K20me1) regulates de novo H4K20 methylation at DSBs. Rapid recruitment of PR-Set7 to DSBs was dependent on the NHEJ Ku70 protein and necessary for NHEJ-directed repair. PR-Set7 monomethyltransferase activity was required, but insufficient, for H4K20me2 and 53BP1 nucleation at DSBs. We determined that PR-Set7-mediated H4K20me1 facilitates Suv4-20 methyltransferase recruitment and catalysis to generate H4K20me2 necessary for 53BP1 binding. The orchestrated and concerted activities of PR-Set7 and Suv4-20 were required for proficient 53BP1 nucleation and DSB repair. This report identifies PR-Set7 as an essential component of NHEJ and implicates PR-Set7 as a central determinant of NHEJ-directed repair early in mammalian DSB repair pathway choice.

Endothelial progenitor cells with Alzheimer's disease.

BACKGROUND: Endothelial dysfunction is thought to be critical events in the pathogenesis of Alzheimer's disease (AD). Endothelial progenitor cells (EPCs) have provided insight into maintaining and repairing endothelial function. To study the relation between EPCs and AD, we explored the number of circulating EPCs in patients with AD. METHODS: A total of 104 patients were recruited from both the outpatients and inpatients of the geriatric neurology department at General Hospital, Tianjin Medical University. Consecutive patients with newly diagnosed AD (n = 30), patients with vascular dementia (VaD, n = 34), and healthy elderly control subjects with normal cognition (n = 40) were enrolled after matching for age, gender, body mass index, medical history, current medication and Mini Mental State Examination. Middle cerebral artery flow velocity was examined with transcranial Doppler. Endothelial function was evaluated according to the level of EPCs, and peripheral blood EPCs was counted by flow cytometry. RESULTS: There were no significant statistical differences of clinical data in AD, VaD and control groups (P > 0.05). The patients with AD showed decreased CD34-positive (CD34(+)) or CD133-positive (CD133(+)) levels compared to the control subjects, but there were no significant statistical differences in patients with AD. The patients with AD had significantly lower CD34(+)CD133(+) EPCs (CD34 and CD133 double positive endothelial progenitor cells) than the control subjects (P < 0.05). In the patients with AD, a lower CD34(+)CD133(+) EPCs count was independently associated with a lower Mini-Mental State Examination score (r = 0.514,P = 0.004). Patients with VaD also showed a significant decrease in CD34(+)CD133(+) EPCs levels, but this was not evidently associated with the Mini-Mental State Examination score. The changes of middle cerebral artery flow velocity were similar between AD and VaD. Middle cerebral artery flow velocity was decreased in the AD and VaD groups and significantly lower than the normal control group (P < 0.01). There was no significant difference of the blood flow velocity between the AD and VaD patients (P > 0.05). CONCLUSIONS: The results provided evidence that patients with AD have reduced circulating EPCs. Endothelial function is impaired in patients with AD and vascular factors have a role in the pathogenesis of AD. CD34(+)CD133(+) EPCs may be a novel biomarker of AD dementia.