Novel CAF-identifiers via transcriptomic and protein level analysis in HNSC patients.

Cancer-associated fibroblasts (CAFs), a prominent component of the tumor microenvironment, play an important role in tumor development, invasion, and drug resistance. The expression of distinct "CAF-markers" which separates CAFs from normal fibroblasts and epithelial cells, have traditionally been used to identify them. These commonly used CAF-markers have been reported to differ greatly across different CAF subpopulations, even within a cancer type. Using an unbiased -omic approach from public data and in-house RNAseq data from patient derived novel CAF cells, TIMP-1, SPARC, COL1A2, COL3A1 and COL1A1 were identified as potential CAF-markers by differential gene expression analysis using publicly available single cell sequencing data and in-house RNAseq data to distinguish CAF populations from tumor epithelia and normal oral fibroblasts. Experimental validation using qPCR and immunofluorescence revealed CAF-specific higher expression of TIMP-1 and COL1A2 as compared to other markers in 5 novel CAF cells, derived from patients of diverse gender, habits and different locations of head and neck squamous cell carcinoma (HNSC). Upon immunohistochemical (IHC) analysis of FFPE blocks however, COL1A2 showed better differential staining between tumor epithelia and tumor stroma. Similar data science driven approach utilizing single cell sequencing and RNAseq data from stabilized CAFs can be employed to identify CAF-markers in various cancers.

Identification of the novel HLA-DPB1*1461:01 allele in three individuals from Southern India.

HLA-DPB1*1461:01 differs from DPB1*02:01:02:01 in exon 2, codon 51 CTG > CGG a Leucine to Arginine replacement.

Estimation of ALU Repetitive Elements in Plasma as a Cost-Effective Liquid Biopsy Tool for Disease Prognosis in Breast Cancer.

BACKGROUND: Liquid biopsy is widely recognized as an efficient diagnostic method in oncology for disease detection and monitoring. Though the examination of circulating tumor cells (CTC) is mostly implemented for the assessment of genomic aberrations, the need of complex methodologies for their detection has impeded its acceptance in low-resource settings. We evaluated cell-free DNA (cfDNA) as a liquid biopsy tool and investigated its utility in breast cancer patients. METHODS: Total cell-free DNA was extracted from the plasma of breast cancer patients (n = 167) with a median follow-up of more than 5 years, at various stages of the disease. Quantitative PCR was performed to estimate the copy numbers of two fractions of ALU repetitive elements (ALU 115 and ALU 247), and DNA integrity (DI) was calculated as the ratio of ALU 247/115. Mutations in TP53 and PIK3CA in the cfDNA were estimated by next-gen sequencing (NGS) in a subset of samples. Associations of the levels of both the ALU fragments with various clinico-pathological factors and disease-free survival at various stages were examined. Nomogram models were constructed with clinical variables and ALU 247 levels to predict disease-free survival and the best performing model was evaluated by decision curve analysis. RESULTS: DI and ALU 247 levels were significantly lower (p < 0.0001) in the post-operative plasma when compared to their pre-surgery levels. DI and ALU 247 were found to be significantly higher in patients with metastasis (p < 0.05). Patients with higher levels of ALU 247 in their post-operative plasma had significant poor disease-free survival (p = 0.005). Higher levels of ALU 247 in the circulation also correlated with low tumor-infiltrating lymphocytes (TIL) within their primary tumors in the ER-negative breast cancer subtype (p = 0.01). Cox proportional hazard analysis confirmed ALU 247 as an independent variable of disease-free survival both in univariate and multivariate analysis [HR 1.3 (95% CI 1.047 to 1.613, p = 0.017)]. The nomogram model showed that the addition of ALU 247 with other variables significantly improved (C-index 0.823) the predictive ability of the model. CONCLUSION: Our results confirm the utility of cfDNA as an evolving liquid biopsy tool for molecular analysis. Evaluation of larger fragments of cfDNA estimated through ALU 247 can provide vital information concurrent with the pathological process of disease evolution in breast cancer and warrants expansion to other cancer types.

Lipocalin 2 inhibits actin glutathionylation to promote invasion and migration.

Invasive and metastatic tumor cells show an increase in migration and invasion, making the processes contributing to these phenotypes potential therapeutic targets. Lipocalin 2 (LCN2; also known as neutrophil gelatinase-associated lipocalin) is a putative therapeutic target in multiple tumor types and promotes invasion and migration, although the mechanisms underlying these phenotypes are unclear. The data in this report demonstrate that LCN2 promotes actin polymerization, invasion, and migration by inhibiting actin glutathionylation. LCN2 inhibits actin glutathionylation by decreasing the levels of reactive oxygen species (ROS) and by reducing intracellular iron levels. Inhibiting LCN2 function leads to increased actin glutathionylation, decreased migration, and decreased invasion. These results suggest that LCN2 is a potential therapeutic target in invasive tumors.

Increased LCN2 (lipocalin 2) in the RPE decreases autophagy and activates inflammasome-ferroptosis processes in a mouse model of dry AMD.

In dry age-related macular degeneration (AMD), LCN2 (lipocalin 2) is upregulated. Whereas LCN2 has been implicated in AMD pathogenesis, the mechanism remains unknown. Here, we report that in retinal pigmented epithelial (RPE) cells, LCN2 regulates macroautophagy/autophagy, in addition to maintaining iron homeostasis. LCN2 binds to ATG4B to form an LCN2-ATG4B-LC3-II complex, thereby regulating ATG4B activity and LC3-II lipidation. Thus, increased LCN2 reduced autophagy flux. Moreover, RPE cells from cryba1 KO, as well as sting1 KO and Sting1Gt mutant mice (models with abnormal iron chelation), showed decreased autophagy flux and increased LCN2, indicative of CGAS- and STING1-mediated inflammasome activation. Live cell imaging of RPE cells with elevated LCN2 also showed a correlation between inflammasome activation and increased fluorescence intensity of the Liperfluo dye, indicative of oxidative stress-induced ferroptosis. Interestingly, both in human AMD patients and in mouse models with a dry AMD-like phenotype (cryba1 cKO and KO), the LCN2 homodimer variant is increased significantly compared to the monomer. Sub-retinal injection of the LCN2 homodimer secreted by RPE cells into NOD-SCID mice leads to retinal degeneration. In addition, we generated an LCN2 monoclonal antibody that neutralizes both the monomer and homodimer variants and rescued autophagy and ferroptosis activities in cryba1 cKO mice. Furthermore, the antibody rescued retinal function in cryba1 cKO mice as assessed by electroretinography. Here, we identify a molecular pathway whereby increased LCN2 elicits pathophysiology in the RPE, cells known to drive dry AMD pathology, thus providing a possible therapeutic strategy for a disease with no current treatment options.Abbreviations: ACTB: actin, beta; Ad-GFP: adenovirus-green fluorescent protein; Ad-LCN2: adenovirus-lipocalin 2; Ad-LCN2-GFP: adenovirus-LCN2-green fluorescent protein; LCN2AKT2: AKT serine/threonine kinase 2; AMBRA1: autophagy and beclin 1 regulator 1; AMD: age-related macular degeneration; ARPE19: adult retinal pigment epithelial cell line-19; Asp278: aspartate 278; ATG4B: autophagy related 4B cysteine peptidase; ATG4C: autophagy related 4C cysteine peptidase; ATG7: autophagy related 7; ATG9B: autophagy related 9B; BLOC-1: biogenesis of lysosomal organelles complex 1; BLOC1S1: biogenesis of lysosomal organelles complex 1 subunit 1; C57BL/6J: C57 black 6J; CGAS: cyclic GMP-AMP synthase; ChQ: chloroquine; cKO: conditional knockout; Cys74: cysteine 74; Dab2: DAB adaptor protein 2; Def: deferoxamine; DHE: dihydroethidium; DMSO: dimethyl sulfoxide; ERG: electroretinography; FAC: ferric ammonium citrate; Fe2+: ferrous; FTH1: ferritin heavy chain 1; GPX: glutathione peroxidase; GST: glutathione S-transferase; H2O2: hydrogen peroxide; His280: histidine 280; IFNL/IFNλ: interferon lambda; IL1B/IL-1ß: interleukin 1 beta; IS: Inner segment; ITGB1/integrin ß1: integrin subunit beta 1; KO: knockout; LC3-GST: microtubule associated protein 1 light chain 3-GST; C-terminal fusion; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; LCN2: lipocalin 2; mAb: monoclonal antibody; MDA: malondialdehyde; MMP9: matrix metallopeptidase 9; NLRP3: NLR family pyrin domain containing 3; NOD-SCID: nonobese diabetic-severe combined immunodeficiency; OS: outer segment; PBS: phosphate-buffered saline; PMEL/PMEL17: premelanosome protein; RFP: red fluorescent protein; rLCN2: recombinant LCN2; ROS: reactive oxygen species; RPE SM: retinal pigmented epithelium spent medium; RPE: retinal pigment epithelium; RSL3: RAS-selective lethal; scRNAseq: single-cell ribonucleic acid sequencing; SD-OCT: spectral domain optical coherence tomography; shRNA: small hairpin ribonucleic acid; SM: spent medium; SOD1: superoxide dismutase 1; SQSTM1/p62: sequestosome 1; STAT1: signal transducer and activator of transcription 1; STING1: stimulator of interferon response cGAMP interactor 1; TYR: tyrosinase; VCL: vinculin; WT: wild type.

Establishment and characterization of novel autologous pair cell lines from two Indian non­habitual tongue carcinoma patients.

Oral tongue squamous cell carcinoma (OTSCC) is one of the major causes of fatality in India due to very high percentage of patients with habits of smoking and chewing tobacco and associated products. Being highly heterogeneous in nature, every patient poses a different challenge clinically. To understand disease progression in an improved way, knowledge of cross­talk between tumor stroma and the tumor cells becomes indispensable. Patient­derived in vitro cell line models are helpful to understand the complexity of diseases. However, they have very low efficiency of establishment from the tumor samples, particularly the cancer­associated fibroblasts (CAFs). In the present study, two novel autologous pairs were immortalized spontaneously from non­habitual, HPV­positive patients, who presented with OTSCC. The epithelial and fibroblast cell lines had typical polygonal and spindle­shaped morphology, respectively. Positive staining with epithelial specific Pan­cytokeratin (PanCK) and fibroblast specific protein (FSP­1) further confirmed their epithelial and fibroblast origin. Unique Short Tandem Repeat (STR) profile of the cultures confirmed their novelty, while the similarity of the STR profiles between the epithelial and fibroblast cells from the same patient, confirmed their autologous nature. DNA analysis revealed aneuploidy of the established cultures. An increase in the tumorigenic potential of the established epithelial cultures upon treatment with CAF­conditioned medium proved the 'CAF­ness' of the established fibroblast cells. The established cultures are the first of their kind which would serve as a useful platform in understanding the tumor­stroma cross­talk in tongue cancer progression.

Low PDL1 Expression in Tumour Infiltrating Lymphocytes Predicts Local Recurrence in Oral Squamous Cell Carcinoma.

In oral squamous cell carcinoma (OSCC), expression of PDL1 is controversial with expressions showing a positive and negative correlation with survival in previous studies. Additionally, it is unclear whether expression on the tumour or tumour infiltrating lymphocytes (TIL) is a better predictor of survival. We performed this study on a cohort of Indian patients with OSCC to determine impact of PDL1 expression on survival. Retrospective analysis of 64 patients of OSCC treated with curative intent surgery with or without adjuvant therapy was performed. Stored tissue blocks were extracted and quantitative immunohistochemistry was performed for PDL1 expression separately on the tumour and the TIL using commercially available Dako kits. Correlation of clinical and pathological variables with PDL1 expression was performed using chi-square test. Survival analysis was performed using Kaplan-Meier method and Cox proportional hazards ratio. In our cohort, PDL1 expression was low, both in tumour (92% had <1% expression) and TIL (56% had <1% expression). Tumour low PDL1 expression (<1%) was associated with a higher risk of lymphovascular invasion (p = 0.044) and bone invasion (p = 0.01) but did not impact survival. Low TIL PDL1 expression (<1%) was more common in younger patients (<45 years) (p = 0.023) significantly predicting local recurrence (p = 0.02). PDL1 expression in OSCC was low. Low TIL PDL1 was common in younger patients and predicted local recurrence. Further study is required to better understand the relationship between age, tumour microenvironment and local recurrence.

Correlation between Radiomorphometric Indices and Edentulous Mandibular Arches to Diagnose Osteoporosis Using Orthopantomogram in West Bengal State in India.

AIM: To assess the influence of gender and age on different parameters of alveolar bone loss using orthopantomogram. MATERIALS AND METHODS: Eighty subjects were enrolled in the study (20 dentulous and 60 completely edentulous), fulfilling the inclusion and exclusion criteria. Completely edentulous subjects were divided into four groups (15 males and 15 females above 60 years) and (15 males and 15 females below 60 years). Dentulous group comprised 20 subjects (10 males and 10 females) between 41 and 75 years. After taking panoramic radiographs, vertical as well as horizontal reference lines were drawn. The parameters used for evaluation included mandibular cortical index (MCI), inferior mandibular cortical width (MCW), panoramic mandibular index (PMI), alveolar bone loss (ABL), and height of bone at first premolar (Hp) and first molar (Hm) of the mandible. RESULTS: There was significant association between MCI and age for females with C2 and C3 categories being more common with advancing age. MCW was stable in all groups, except in females above 60 years of age. PMI and ABL were nonsignificant for age and gender. Although the average values of bone height (Hm and Hp) for males were higher than those of females, the results were statistically insignificant. CONCLUSION: Panoramic radiographic measurements could provide much valuable information and could help in evaluating patients with a low bone mineral density (BMD) with a few limitations. CLINICAL SIGNIFICANCE: Dental professionals could screen the patients through panoramic radiographs taken during routine clinical examination, which could help in identifying patients with a low BMD so that further treatment could be initiated early and thus to prevent a pathologic fracture.

Lipocalin 2 expression promotes tumor progression and therapy resistance by inhibiting ferroptosis in colorectal cancer.

Lipocalin 2 is a siderophore-binding protein that regulates iron homeostasis. Lipocalin 2 expression is elevated in multiple tumor types; however, the mechanisms that drive tumor progression upon Lipocalin 2 expression remain unclear. When Lipocalin 2 is over-expressed, it leads to resistance to 5-fluorouracil in colon cancer cell lines in vitro and in vivo by inhibiting ferroptosis. Lipocalin 2 inhibits ferroptosis by decreasing intracellular iron levels and stimulating the expression of glutathione peroxidase4 and a component of the cysteine glutamate antiporter, xCT. The increase in xCT levels is dependent on increased levels of ETS1 in Lipocalin 2 over-expressing cells. Inhibiting Lipocalin 2 function with a monoclonal antibody leads to a decrease in chemo-resistance and transformation in vitro, and a decrease in tumor progression and chemo-resistance in xenograft mouse models. Lipocalin 2 and xCT levels exhibit a positive correlation in human tumor samples suggesting that the pathway we have identified in cell lines is operative in human tumor samples. These results indicate that Lipocalin 2 is a potential therapeutic target and that the monoclonal antibody described in our study can serve as the basis for a potential therapeutic in patients who do not respond to chemotherapy.

Correlation of Cry1Ac mRNA and protein abundance in transgenic Gossypium hirsutum plant.

Transcription and translation in eukaryotes are distinct processes of the molecular cascade leading to protein production from genetic material. However, establishing correlation between mRNA expression and protein abundance, the end results of the two processes of central dogma, remains a challenge. For transgenic plants, such correlation between mRNA and protein expression serves as a guide to design the transgene, in particular the choices of promoter and codon usage to ensure stable expression of the target protein in relevant tissues under various stress conditions. To elucidate level of mRNA-protein correlation in a commercial transgenic cotton plant Gossypium hirsutum, Bollgard II® (MON15985), we present the results of Cry1Ac protein expression correlating with corresponding mRNA levels. Protein was quantitated using a home-grown validated ELISA assay with a monoclonal-polyclonal antibody pair, whereas mRNA level was detected by a real-time quantitative PCR assay using standardized reference genes. Our results indicate that protein and mRNA levels are highly correlated in the leaves, but not in squares and stem. The correlations seem to be consistent between young and mature leaves and increase over time of harvesting of samples from months 1-3. These findings demonstrate that transcript level measurement could serve as a proxy to protein abundance for this commercially important cotton species, particularly for leaf tissues which are the most vulnerable organs to cotton bollworms and other pathogens. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-02828-2.

Case Report of a Rare Incidence of IgH Amplification Leading to Acute Kidney Injury in a Multiple Myeloma Patient.

We present a case report of a 62-year-old male, treated for kappa light chain multiple myeloma with chemotherapy followed by autologous stem cell transplant (ASCT) in 2014. He has been in complete remission for 4 years. In 2018, he was evaluated for hypercreatinemia and acute kidney injury(AKI) with a suspicion of disease relapse; he underwent evaluation with bone marrow aspiration cytology which showed no evidence of relapse. However, careful cytogenetic analyses showed IgH amplification (14q32) which probably was the cause for AKI in the absence of any structural abnormality in the kidney. Heavy chain deposition leads to AKI in multiple myeloma, and its association with IgH amplification leading to AKI is reported here. Though heavy chain deposition leading to AKI is common, IgH amplification at chromosome level is the first case observed.

IL-6 and IL-10 as predictors of disease severity in COVID-19 patients: results from meta-analysis and regression.

AIMS: SARS-CoV-2, an infectious agent behind the ongoing COVID-19 pandemic, induces high levels of cytokines such as IL-1, IL-2, IL-4, IL-6, IL-10, TNF-α, IFN-γ etc in infected individuals that play a role in the underlying patho-physiology. Nonetheless, exact association and contribution of every cytokine towards COVID-19 pathology remains poorly understood. Delineation of the roles of cytokines during COVID-19 holds the key to efficient patient management in clinics. This study performed a comprehensive meta-analysis to establish association between induced cytokines and COVID-19 disease severity to help in prognosis and clinical care. MAIN METHODS: Scientific literature was searched to identify 13 cytokines (IL-1ß, IL-2, IL-2R, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12, IL-17, TNF-α and IFN-γ) from 18 clinical studies. Standardized mean difference (SMD) for selected 6 cytokines IL-2, IL-4, IL-6, IL-10, TNF-α and IFN-γ between severe and non-severe COVID-19 patient groups were summarized using random effects model. A classifier was built using logistic regression model with cytokines having significant SMD as covariates. KEY FINDINGS: Out of the 13 cytokines, IL-6 and IL-10 showed statistically significant SMD across studies synthesized. Classifier with mean values of both IL-6 and IL-10 as covariates performed well with accuracy of ~92% that was significantly higher than accuracy reported in literature with IL-6 and IL-10 as individual covariates. SIGNIFICANCE: Simple panel proposed by us with only two cytokine markers can be used as predictors for fast diagnosis of patients with higher risk of COVID-19 disease deterioration and thus can be managed well for a favourable prognosis.

Relative quantification of BCL2 mRNA for diagnostic usage needs stable uncontrolled genes as reference.

Dysregulation of BCL2 is a pathophysiology observed in haematological malignancies. For implementation of available treatment-options it is preferred to know the relative quantification of BCL2 mRNA with appropriate reference genes. For the choice of reference genes-(i) Reference Genes were selected by assessing variation of >60,000 genes from 4 RNA-seq datasets of haematological malignancies followed by filtering based on their GO biological process annotations and proximity of their chromosomal locations to known disease translocations. Selected genes were experimentally validated across various haematological malignancy samples followed by stability comparison using geNorm, NormFinder, BestKeeper and RefFinder. (ii) 43 commonly used Reference Genes were obtained from literature through extensive systematic review. Levels of BCL2 mRNA was assessed by qPCR normalized either by novel reference genes from this study or GAPDH, the most cited reference gene in literature and compared. The analysis showed PTCD2, PPP1R3B and FBXW9 to be the most unregulated genes across lymph-nodes, bone marrow and PBMC samples unlike the Reference Genes used in literature. BCL2 mRNA level shows a consistent higher expression in haematological malignancy patients when normalized by these novel Reference Genes as opposed to GAPDH, the most cited Reference Gene. These reference genes should also be applicable in qPCR platforms using Taqman probes and other model systems including cell lines and rodent models. Absence of sample from healthy-normal individual in diagnostic cases call for careful selection of Reference Genes for relative quantification of a biomarker by qPCR.BCL2 can be used as molecular diagnostics only if normalized with a set of reference genes with stable yet low levels of expression across different types of haematological malignancies.

Usage of Graphene Oxide in Fluorescence Quenching-Linked Immunosorbent Assay for the Detection of Cry2Ab Protein Present in Transgenic Plants.

Graphene oxide-based sensor technologies in various detection platforms have been adopted in multiple dimensions. Most of the applications in combination with other materials such as gold, silver, enzymes, and so forth are read as electrical, electrochemical, impedance, and fluorescence signals. We report the development of a novel and simple fluorescence quenching-based immunoassay platform that provides quantitative binding sites for the Cry2Ab protein content present in the transgenic cotton (Gossypium hirsutum) plant. In this assay, the graphene oxide-conjugated anti-Cry2Ab antibody serves as the binding site for the analyte Cry2Ab protein, which forms a complex with a second anti-Cry2Ab fluorescein isothiocyanate (FITC)-conjugated antibody. This complex acts as the reaction center of this platform where the graphene oxide quenches the fluorescence signal of the FITC molecule. This microtiter plate-based method currently works at a sensitivity of 0.78 ng /ml, which can further be improved.

Neutrophils homing into the retina trigger pathology in early age-related macular degeneration.

Age-related macular degeneration (AMD) is an expanding problem as longevity increases worldwide. While inflammation clearly contributes to vision loss in AMD, the mechanism remains controversial. Here we show that neutrophils are important in this inflammatory process. In the retinas of both early AMD patients and in a mouse model with an early AMD-like phenotype, we show neutrophil infiltration. Such infiltration was confirmed experimentally using ribbon-scanning confocal microscopy (RSCM) and IFNλ- activated dye labeled normal neutrophils. With neutrophils lacking lipocalin-2 (LCN-2), infiltration was greatly reduced. Further, increased levels of IFNλ in early AMD trigger neutrophil activation and LCN-2 upregulation. LCN-2 promotes inflammation by modulating integrin ß1 levels to stimulate adhesion and transmigration of activated neutrophils into the retina. We show that in the mouse model, inhibiting AKT2 neutralizes IFNλ inflammatory signals, reduces LCN-2-mediated neutrophil infiltration, and reverses early AMD-like phenotype changes. Thus, AKT2 inhibitors may have therapeutic potential in early, dry AMD.

Genome wide search to identify reference genes candidates for gene expression analysis in Gossypium hirsutum.

BACKGROUND: Cotton is one of the most important commercial crops as the source of natural fiber, oil and fodder. To protect it from harmful pest populations number of newer transgenic lines have been developed. For quick expression checks in successful agriculture qPCR (quantitative polymerase chain reaction) have become extremely popular. The selection of appropriate reference genes plays a critical role in the outcome of such experiments as the method quantifies expression of the target gene in comparison with the reference. Traditionally most commonly used reference genes are the "house-keeping genes", involved in basic cellular processes. However, expression levels of such genes often vary in response to experimental conditions, forcing the researchers to validate the reference genes for every experimental platform. This study presents a data science driven unbiased genome-wide search for the selection of reference genes by assessing variation of > 50,000 genes in a publicly available RNA-seq dataset of cotton species Gossypium hirsutum. RESULT: Five genes (TMN5, TBL6, UTR5B, AT1g65240 and CYP76B6) identified by data-science driven analysis, along with two commonly used reference genes found in literature (PP2A1 and UBQ14) were taken through qPCR in a set of 33 experimental samples consisting of different tissues (leaves, square, stem and root), different stages of leaf (young and mature) and square development (small, medium and large) in both transgenic and non-transgenic plants. Expression stability of the genes was evaluated using four algorithms - geNorm, BestKeeper, NormFinder and RefFinder. CONCLUSION: Based on the results we recommend the usage of TMN5 and TBL6 as the optimal candidate reference genes in qPCR experiments with normal and transgenic cotton plant tissues. AT1g65240 and PP2A1 can also be used if expression study includes squares. This study, for the first time successfully displays a data science driven genome-wide search method followed by experimental validation as a method of choice for selection of stable reference genes over the selection based on function alone.

To Compare and Evaluate the Sorption and Solubility of Four Luting Cements after Immersion in Artificial Saliva of Different pH Values.

INTRODUCTION: The word 'luting' is derived from a latin word 'Lutum' which means 'mud'. 'Luting' is a word that is often used to describe the use of a mouldable substance to seal a space or to cement two components together. Therefore in view of the clinical importance of dissolution of luting cements in the oral environment, an in vitro study was designed to compare the sorption and solubility of commercially available luting cements mainly zinc phosphate, Glass Ionomer cement, Resin Modified Glass Ionomer Cement and Resin Cement after immersion in artificial saliva of different ph values of 5 and 7. AIM: To Compare and Evaluate the sorption and solubility of four luting cements after immersion in artificial saliva of different pH values. MATERIALS AND METHOD: A total of 120 test samples were prepared of which 30 samples of each luting cement were prepared for the purpose of assessing the water solubility and sorptionThese luting cements were grouped as: GROUP- A (Zinc Phosphate cement), GROUP- B (Glass Ionomer Cement), GROUP-C (Resin Modified Cement), GROUP- D (Resin Cement) In these groups, based on immersion of artificial saliva of acidic pH 5 and neutral pH7, the luting cement specimens were subdivided into 2 groups of 15 samples each. The volume (V) of each specimen was calculated using mathematical formula. CONCLUSION: Resin cement had the highest resistance to solubility and sorption followed by resin modified GIC, Conventional GIC, and Zinc Phosphate which exhibited the least resistance to solubility in both artificial saliva of pH 5 and pH 7.