Hydrothermal alteration of the surface volcanic rocks at the Acoculco geothermal field,Mexico:a multi-parametric approach

The studies on hydrothermal alteration-induced eff ects in surface and subsurface rocks provide useful information in the characterization and exploitation of a geothermal reservoir.Generally,these studies are based on traditional,and reliable methods like petrography(primary and secondary minerals,and grade of alteration),and geochemistry(mobility of elements,changes in mass and concentration of elements,and fluid inclusions).Recently,apart from these established methods,some methods based on the geochemical(Chemical Index of Alteration,CIA;Weathering Index of Parkar,WIP;Loss on Ignition,LOI;and Sulfur,S)and rock magnetic properties(magnetic susceptibility,χlf;and percentage frequency-dependent susceptibility,χfd%)are also being applied in the identification of whether a rock is an altered or a fresh one.The Acoculco Geothermal Field(AGF),Mexico,is characterized by high temperature and very low permeability,and it is considered a promissory Enhanced Geothermal System.The following changes are observed in the rocks as a result of an increase in hydrothermal alteration:(1)an increase in CIA,LOI,and S values,and a decrease in WIP;(2)an increase in quartz and quartz polymorph minerals(silicification),and clay minerals(argillization);and(3)decrease inχlf values.At AGF,the most altered surface acid rocks are characterized by entirely quartz and its polymorphs,and clay minerals.The present study also indicates the applicability of the binary plots of major elements(felsic vs mafic component)and rock magnetic parameters(χlf vs.χfd%).The rock withχfd%value of 2-10 andχlf value<0.5×10^(-6)m^(3) kg^(-1)indicate the presence of single domain and stable single domain grains,which in turn suggests that it is an altered rock.These methods are simple to apply,rapid,reliable,and have the potential to become eff ective tools for the identifi cation of hydrothermally altered rocks during the initial stage of geothermal exploration.

Risk stratification for radioactive iodine refractoriness using molecular alterations in distant metastatic differentiated thyroid cancer

Objective: Patients with radioactive iodine-refractory differentiated thyroid cancer(RAIR-DTC) are often diagnosed with delay and constrained to limited treatment options. The correlation between RAI refractoriness and the underlying genetic characteristics has not been extensively studied.Methods: Adult patients with distant metastatic DTC were enrolled and assigned to undergo next-generation sequencing of a customized 26-gene panel(Thyro Lead). Patients were classified into RAIR-DTC or non-RAIR groups to determine the differences in clinicopathological and molecular characteristics. Molecular risk stratification(MRS) was constructed based on the association between molecular alterations identified and RAI refractoriness, and the results were classified as high, intermediate or low MRS.Results: A total of 220 patients with distant metastases were included, 63.2% of whom were identified as RAIRDTC. Genetic alterations were identified in 90% of all the patients, with BRAF(59.7% vs. 17.3%), TERT promoter(43.9% vs. 7.4%), and TP53 mutations(11.5% vs. 3.7%) being more prevalent in the RAIR-DTC group than in the non-RAIR group, except for RET fusions(15.8% vs. 39.5%), which had the opposite pattern. BRAF and TERT promoter are independent predictors of RAIR-DTC, accounting for 67.6% of patients with RAIR-DTC. MRS was strongly associated with RAI refractoriness(P<0.001), with an odds ratio(OR) of high to low MRS of 7.52 [95%confidence interval(95% CI), 3.96-14.28;P<0.001] and an OR of intermediate to low MRS of 3.20(95% CI,1.01-10.14;P=0.041).Conclusions: Molecular alterations were associated with RAI refractoriness, with BRAF and TERT promoter mutations being the predominant contributors, followed by TP53 and DICER1 mutations. MRS might serve as a valuable tool for both prognosticating clinical outcomes and directing precision-based therapeutic interventions.

Identifying Comprehensive Genomic Alterations and Potential Neoantigens for Cervical Cancer Immunotherapy in a Cohort of Chinese Squamous Cell Carcinoma of the Cervix

Objective Genomic alterations and potential neoantigens for cervical cancer immunotherapy were identified in a cohort of Chinese patients with cervical squamous cell carcinoma(CSCC).Methods Whole-exome sequencing was used to identify genomic alterations and potential neoantigens for CSCC immunotherapy.RNA Sequencing was performed to analyze neoantigen expression.Results Systematic bioinformatics analysis showed that C>T/G>A transitions/transversions were dominant in CSCCs.Missense mutations were the most frequent types of somatic mutation in the coding sequence regions.Mutational signature analysis detected signature 2,signature 6,and signature 7 in CSCC samples.PIK3CA,FBXW7,and BICRA were identified as potential driver genes,with BICRA as a newly reported gene.Genomic variation profiling identified 4,960 potential neoantigens,of which 114 were listed in two neoantigen-related databases.Conclusion The present findings contribute to our understanding of the genomic characteristics of CSCC and provide a foundation for the development of new biotechnology methods for individualized immunotherapy in CSCC.

Genomic alterations in oral multiple primary cancers

Oral squamous cell carcinoma (OSCC) is the predominant type of oral cancer, while some patients may develop oral multiple primary cancers (MPCs) with unclear etiology. This study aimed to investigate the clinicopathological characteristics and genomic alterations of oral MPCs. Clinicopathological data from patients with oral single primary carcinoma (SPC, n=202) and oral MPCs (n=34) were collected and compared. Copy number alteration (CNA) analysis was conducted to identify chromosomal-instability differences among oral MPCs, recurrent OSCC cases, and OSCC patients with lymph node metastasis. Whole-exome sequencing was employed to identify potential unique gene mutations in oral MPCs patients. Additionally, CNA and phylogenetic tree analyses were used to gain preliminary insights into the molecular characteristics of different primary tumors within individual patients. Our findings revealed that, in contrast to oral SPC, females predominated the oral MPCs (70.59%), while smoking and alcohol use were not frequent in MPCs.Moreover, long-term survival outcomes were poorer in oral MPCs. From a CNA perspective, no significant differences were observed between oral MPCs patients and those with recurrence and lymph node metastasis. In addition to commonly mutated genes such as CASP8, TP53 and MUC16, in oral MPCs we also detected relatively rare mutations, such as HS3ST6 and RFPL4A. Furthermore, this study also demonstrated that most MPCs patients exhibited similarities in certain genomic regions within individuals, and distinct differences of the similarity degree were observed between synchronous and metachronous oral MPCs.

Sex-dependent alterations in extracellular vesicles linking chronic spinal cord injury to brain neuroinflammation and neurodegeneration

Traumatic spinal cord injury(SCI)is a devastating exogenous injury with long-lasting consequences and a leading cause of death and disability worldwide.Advances in assistive technology,rehabilitative interventions,and the ability to identify and intervene in secondary conditions have significantly increased the long-term survival rate of SCI patients,with some people even living well into their seventh or eighth decade.These survival changes have led neurotrauma researchers to examine how SCI interacts with brain aging.Public health and epidemiological data showed that patients with long-term SCI can have a lower life expectancy and quality of life,along with a higher risk of comorbidities and complications.

Clinicopathological alterations in wild mammals from the reservoir system of Trypanosoma cruzi:a scoping review

Trypanosoma cruzi is the etiologic agent of Chagas disease.This flagellated protozoan is transmitted to humans as well as different species of domestic and wild animals via vectors from the Reduviidae family(known as"kissing bugs").Despite the fact that hundreds of species of wild mammals are part of the reservoir system,the morphologi-cal changes and clinical manifestations resulting from the pathogenesis of the infection have been largely neglected.The aim of this review is to systematically compile the available information regarding clinicopathological altera-tions in wild mammals due to natural infection by T.cruzi.Information was obtained from six online bibliographic data search platforms,resulting in the identification of 29 publications that met the inclusion criteria.Mortality was the most common clinical manifestation,cardiac damage was the main finding at necropsy,and lymphoplas-macytic inflammation was the most frequent microscopic injury.Thus,regardless of its role as a reservoir,T.cruzi has the potential to affect the health status of wild mammals,a situation that highlights the need for further research to analyze,measure,and compare its effects at both the individual and population levels.

Bilateral meibomian gland morphological alterations in unilateral herpes simplex keratitis based on artificial intelligence analysis

AIM:To explore whether unilateral herpes simplex keratitis(HSK)can cause morphological changes of bilateral meibomian glands(MGs)based on artificial intelligence(AI)analytical system.METHODS:In the retrospective study,29 patients with unilateral HSK and 29 participants matched in terms of age and sex were included as control group.Meibographic images of the upper eyelid using Keratograph 5M and assessed ocular surface parameters including tear meniscus height and tear break-up time.MG density and vagueness values were automatically analyzed and calculated using an AI analytical system.We compared the differences between the affected and the contralateral unaffected eyes in HSK patients,and the normal control eyes.We employed either the paired t-test or the Wilcoxon signed-rank test to compare significant difference between the affected and unaffected eyes in HSK patients or between the HSK group and control group.RESULTS:The MG density was 0.19±0.09 in the HSKaffected eye and 0.18±0.07 in contralateral unaffected eye,which had no significant difference(P=0.616).The MG density between the affected eye with HSK and the normal control group was statistically significant(P=0.028).There was a significant difference in MG density between the contralateral unaffected eye and the normal control group(P=0.012).However,no significant difference in vagueness value was observed between the eye with HSK and the control group or between HSK eye and contralateral eye.CONCLUSION:The MG density between the HSKaffected eye and the contralateral unaffected eye don’t significantly differ,whereas there is a significant decrease in the HSK group compared to that of the normal participants.Unilateral HSV keratitis may suffer from bilateral changes of MG morphology indicating bilateral dry eye.Therefore,the fellow eye of patients with unilateral HSK should be considered a potential case of MG dysfunction,necessitating early treatment for bilateral dry eye in the clinic.

Application of Remote Sensing and GIS in Mineral Alteration Mapping and Lineament Extraction Case of Oudiane Elkharoub (Requibat Shield, Northern of Mauritania)

The integration of remotely sensed data allowed the successful characterization of the mineral alteration zones of the Oudiane Elkharoub area in the Northeastern part of Reguibat Shield using image transformation techniques. As both chemical and geochemical analyses showed significant Au, Ag, Cu, Pb, Mn, Cr, Ni, Th and Y anomalies, it’s very interesting to apply the remote sensing and GIS in mineral resources mapping. The remote sensing is a direct adjunct to the field, lithologic and structural mapping, and more recently, GIS has played an important role in the study of mineralization areas. The integration of several evidential maps highlighted the plausible areas with high concentrations of chlorite, epidote, kaolinite, calcite, alunite, hematite, illite and sulfur among other key mineral alterations that reflect the intensity of hydrothermal effects and the probable sites of ore bodies. The methodological approach integrates geological information acquired from Aster and Landsat 8 OLI/TIRS (Operational Land Imager/Thermal InfraRed Sensor) images and a multi-criteria GIS analysis. The superimposition of various lineament and hydrothermal alteration maps and the consideration of precious and base metal indicators allowed the zoning of sites likely to contain mineral concentrations. Remote sensing becomes an important tool for locating mineral deposits in its own right, when the primary and secondary processes of mineralization result in the formation of spectral anomalies. Reconnaissance lithological mapping is usually the first step of mineral resource mapping. This is complimented with structural mapping, as mineral deposits usually occur along or adjacent to geologic structures, and alteration mapping, as mineral deposits are commonly associated with hydrothermal alteration of the surrounding rocks. Ground truthing and laboratory studies including XRD analysis were utilized to verify the results.

Hematological Alterations in an Eastern Sudanese Chronic Kidney Disease Patient Population

Background: Chronic Kidney Disease (CKD), associated with a slow and progressive loss of kidney function over a period of several years, is an important clinical disaster with an increasing rate of morbidity and mortality especially in the least developed countries. Many hematological parameters are thought to alter dramatically during the course of the disease. These include white blood cells, red blood cells, and platelets. Methods: We tried, retrospectively, to evaluate the peripheral blood hematological alterations in a group of patients undergoing hemodialysis in an eastern Sudan dialysis center to add local medical information. Results: Anemia (Low hemoglobin and hematocrit) was detected in 94% of the patients’ group. Mean Erythrocyte count (3.32vs.4.76 (×109/L)), Hemoglobin concentration (9.4vs.13 (g/dl)), Hematocrit (28.7vs.38.7 (L/L)) and platelet count (296 vs. 238 (×109/L)) were significantly lower in the patients’ group than in the control group (P-values Conclusion: Five out of eight studied parameters (Red cell count, hemoglobin, hematocrit, mean cell hemoglobin concentration, and platelets count) have shown a significant alteration in CKD patients. As the complete blood count (CBC) test is the most utilized test in clinical laboratory practice, these alterations may be considered as early indicators for CKD. Furthermore, all patients with CKD must be routinely checked for these alterations.

Evaluation of the coupled impact of silicon oxide nanoparticles and low-salinity water on the wettability alteration of Berea sandstones

This study investigated experimentally the coupled effects of hydrophilic SiO_(2) nanoparticles(NPs)and low-salinity water(LSW)on the wettability of synthetic clay-free Berea sandstone.Capillary pressure,interfacial tension(IFT),contact angle,Zeta potential,and dynamic displacement measurements were performed at various NP mass fractions and brine salinities.The U.S.Bureau of Mines(USBM)index was used to quantify the wettability alteration.Furthermore,the NP stability and retention and the effect of enhanced oil recovery by nanofluid were examined.The results showed that LSW immiscible displacement with NPs altered the wettability toward more water wet.With the decreasing brine salinity and increasing NP mass fraction,the IFT and contact angle decreased.The wettability alteration intensified most as the brine salinity decreased to 4000 mg/L and the NP mass fraction increased to 0.075%.Under these conditions,the resulting incremental oil recovery factor was approximately 13 percentage points.When the brine salinity was 4000 mg/L and the NP mass fraction was 0.025%,the retention of NPs caused the minimum damage to permeability.

Wettability alteration of organo-vermiculites induced by layer charge and tailored bis-N-heterocyclic quaternary ammonium salts

Wettability is an important surface property that deserves to further explore the factors on its alteration.Series of bis-N-heterocyclic quaternary ammonium salts with different spacer length and N-heterocyclic headgroups(morpholinium(BMMB,BMMD and BMMH),piperidinium(BPMH)and piperazinium(BMPMH))have been synthesized and employed for altering the wettability of vermiculite and its derivates(Vts)treated by Li^(+)-saturated heating method.The results of X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),thermogravimetric analysis(TG-DTG),scanning electron microscopy(SEM)and N_(2)adsorption/desorption isotherms indicate that all of the bis-N-heterocyclic quaternary ammonium salts have been successfully inserted into the vermiculite layers,leading to the organic monolayer.The results of capillary rise tests combined with Lipophilic to Hydrophilic Ratio(LHR)values unveil the wettability alteration of the organo-Vts.As the layer charge decreases,the hydrophilicity of the organo-Vts gradually increases,which is probably caused by the decline in binding sites.As the result of the change in spacer length of modifier,the wetting properties of morpholinium-based organo-Vts change in order of BMMD-Vts>BMMH-Vts>BMMB-Vts,and difference in N-heterocyclic headgroups leads to the sequence of wettability:BMPMH-Vts>BPMH-Vts>BMMH-Vts.Layer charge of Vt,spacer length and the type of the N-heterocyclic headgroup of modifier have the synergistic effect on the regulation of the wettability.

Investigation of the effect of diethylene triamine pentaacetic acid chelating agent as an enhanced oil recovery fluid on wettability alteration of sandstone rocks

This study used the diethylene triamine pentaacetic acid(DTPA)-seawater(SW)system to modify the sandstone rock wettability and enhance oil recovery.The investigation involved conducting wettability measurement,Zeta potential measurement,and spontaneous imbibition experiment.The introduction of 5%DTPA-sW solution resulted in a significant decrease in the rock-oil contact angle from 143°to 23,along with a reduction in the Zeta potential from-2.29 mV to-13.06 mV,thereby altering the rock surface charge and shifting its wettability from an oil-wet state to a strongly water-wet state.The presence or absence of potential determining ions(Ca^(2+),Mg^(2+),SO_(4)^(2-))in the solution did not impact the effectiveness of DTPA in changing the rock wettability.However,by tripling the concentration of these ions in the solution,the performance of 5%DTPA-SW solution in changing wettability was impaired.Additionally,spontaneous imbibition tests demonstrated that the 5%DTPA-SW solution led to an increase in oil recovery up to 39.6%.Thus,the optimum mass fraction of DTPA for changing sandstone wettability was determined to be5%.

Synaptic alterations as a common phase in neurological and neurodevelopmental diseases: JNK is a key mediator in synaptic changes

Brain synapses play a key role in neuronal communication:this“conversation”is at the basis of all brain activities and synaptic dysfunction leads to brain disorders.We study the modulators of this crucial synaptic function and we here present the evidence supporting the c-Jun N-terminal kinase(JNK)pathway as a pivotal actor in this scenario.

Insight into the evolution of breast cancer driven by genetic alterations

Breast cancer originates primarily from the epithelial cells of the mammary gland.Repeated mammary gland expansion and degeneration are accompanied by an increased risk of genetic alterations in the breast1.These mutations in breast epithelial cells dynamically occur in response to pregnancy,labor and delivery,breastfeeding,and the menstrual cycle,with a decline in mutation rates after menopause,which may be related to a decrease in estrogen levels.The breast epithelial cell mutations are also consistent with epidemiologic observations2.

Integrating Aster Images Processing and Fieldwork for Identification of Hydrothermal Alteration Zones at the Oumjrane-Boukerzia District, Moroccan Anti-Atlas

Mapping from remote sensing has become more effective in the field of geology, mainly in lithological discrimination and identification of hydrothermal alteration zones. The use of this technique consists in obtaining information about the rock mass and the main ones existing in the inaccessible areas. Satellite data from the ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) sensor represent a favorable potential for detecting the spectral signatures of mineral zones and identifying their nature. These data are more reliable in places where the climate is arid with less abundant vegetation, as at the Oumjrane-Boukerzia mining district. This region which is part of the Eastern Anti-Atlas, is composed of several mineralized veins which still require detailed studies and exploration by the technique of remote sensing. In this work we applied several processing techniques on ASTER imagery such as Colored Composition, Principal Component Analysis and Ratio Bands. The use of the reports of the specialized Bands makes it possible to identify some hydrothermal alteration minerals within the mining district of Oumjrane Boukerzia. These minerals are represented mainly by iron oxides and hydroxides (Hematite, jarosite, limonite and goethite), carbonate minerals (dolomite, calcite), clay minerals (Illite, kaolinite and chlorite) and quartz minerals. This work allows us to produce a map of hydrothermal alteration zones which can be used as a valuable reference in the strategy of mining exploration for the base metals (Cu, Pb, Zn and Ba), in the mining district of Oumjrane-Boukerzia and in the entire Eastern Anti-Atlas.

ASTER Data Processing by Discrete Wavelets Transform and Band Ratio Techniques for the Identification of Lineaments and Hydrothermal Alteration Zones in Poli, North Cameroon

The aim of this study is to carry out hydrothermal alteration mapping and structural mapping using ASTER images in order to identify indices that could guide mining exploration work in the Poli area and its surroundings. To achieve this, the ASTER images were first preprocessed to correct atmospheric effects and remove vegetation influence. Secondly, a lineament mapping was conducted by applying Discrete Wavelet Transform (DWT) algorithms to the First Principal Component Analysis (PCA1) of Visible Near-Infrared (VNIR) and Shortwave Infrared (SWIR) bands. Lastly, band ratio methods were applied to the VNIR, SWIR, and Thermal Infrared (TIR) bands to determine indices of iron oxides/hydroxides (hematite and limonite), hydroxyl-bearing minerals (chlorite, epidote, and muscovite), and the quartz index. The results obtained showed that the lineaments were mainly oriented NE-SW, ENE-WSW, and E-W, with NE-SW being the most predominant direction. Concerning hydrothermal alteration, the identified indices covered almost the entire study area and showed a strong correlation with lithological data. Overlaying the obtained lineaments with the hydrothermal alteration indices revealed a significant correlation between existing mining indices and those observed in the field. Mineralized zones generally coincided with areas of high lineament density exhibiting significant hydrothermal alteration. Based on the correlation between existing mining indices and the results of hydrothermal and structural mapping, the results obtained can then be used as a reference document for any mining exploration in the study area.

Alteration Typology and Geochemical Signatures of the Napélépéra Gold-Bearing Granodiorite in South-West Burkina Faso (West Africa)

The characterization of the relationships between mineralization and hydrothermal alteration is an essential element in understanding gold deposits. In south-west Burkina Faso, the Napélépéra mineralisation, the mobility of chemical elements and alteration-mineralization relationships were studied by means of selected core drilling and geochemical analyses using ICP-MS (Inductively Coupled Plasma Mass Spectrometry) and ICP-AES (Inductively coupled plasma atomic emission spectroscopy). The mineralised granodiorite is grey porphyroid with quartz, plagioclase, biotite and amphibole. It is metaluminous and located in the tholeiitic series. The Na2O + CaO versus Fe2O3 + MgO alteration diagram divides the samples according to alteration dominance. Chloritisation and carbonation are the main alterations. There is a relationship between gold mineralisation at Napélépéra and alteration, and the paragenesis of gold + pyrite ± carbonate ± silica ± sericite is the main characteristic. Carbonation is the result of fluid input in the shear corridor of the mineralised zone. The mass balance of comparative metals in the proximal and distal zones of the mineralisation shows the absence of metals, while As, Hg, Ag and Bi are strongly enriched from the distal zone to the mineralised zone. The oxides associated with the mineralisation are mainly NaO, SrO and CaO.

Extraction of Mineral Alteration Zone from ETM+ Data in Northwestern Yunnan,China

Alteration is regarded as significant information for mineral exploration. In this study, ETM＋ remote sensing data are used for recognizing and extracting alteration zones in northwestern Yunnan （云南）, China. The principal component analysis （PCA） of ETM＋ bands 1, 4, 5, and 7 was employed for OH alteration extractions. The PCA of ETM＋ bands 1, 3, 4, and 5 was used for extracting Fe^2＋ （Fe^3＋） alterations. Interfering factors, such as vegetation, snow, and shadows, were masked. Alteration components were defined in the principal components （PCs） by the contributions of their diagnostic spectral bands. The zones of alteration identified from remote sensing were analyzed in detail along with geological surveys and field verification. The results show that the OH^- alteration is a main indicator of K-feldspar, phyllic, and prophilized alterations. These alterations are closely related to porphyry copper deposits. The Fe^2＋ （Fe^3＋） alteration indicates pyritization, which is mainly related to hydrothermal or skarn type polymetallic deposits.

Characterization of Fertility Alteration in 8 Environment-sensitive Genic Male-sterile Lines of indica Rice

Eight indica ( Oryza sativa L.) environment-sensitive genic male-sterile (EGMS) lines, 2-2S, K1405S, F131S, 2136S, Pei-Ai 64S, 1290S, GD-IS and N17S, were sequentially seeded with 10-15 d interval at three sites, Wuhan in 1997, Guiyang in 1997 and Sanya in 1997 and 1998, China. The results of investigations on self-sterilities showed that all of eight EGMS lines had stable sterile periods of longer than 30 d at Wuhan. They can be used for seed production of two-line hybrid rice, but can not reproduce themselves. Their stable sterile periods were shorter than 30 d at Guiyang, they can reproduce themselves and can not be used for hybrid seed production. In Sanya, their stable sterile periods were longer than 150 d, all of eight lines can be used for seed production in summer and autumn and reproduce themselves in winter. The fertility of all eight lines were sensitive to temperature. The sensitive stages, sensitive duration and critical point of temperatures (CPT) of fertility alteration in various lines were different. The sensitive stages of 2-2S and K1405S were from 18 d to 9 d before heading, the sensitive durations were 7-10 d and the CPTs were 23.7-24.5 degreesC. The sensitive stage, sensitive duration and CPT of F131S were from 17 to 5 d before heading, 13 d and 24.3-24.7 degreesC, respectively. The sensitive stage, sensitive duration and CPT of 2136S were from 18 to 12 d before heading, 7 d and 24.6-25.1 degreesC:, respectively. The sensitive stages, sensitive durations of Pei-Ai 64S, 1290S, N17S and GD-1S were from 24 to 13 d before heading and 10-13 d. And their CPTs were 24.6-25.1 degreesC, 25.5-26.2 degreesC, 25.4-26.1 degreesC,, and 24.1-24.7 degreesC, respectively.

Molecular alterations in gastric cancer with special reference to the early-onset subtype

Currently, gastric cancer(GC) is one of the most frequently diagnosed neoplasms, with a global burden of 723000 deaths in 2012. It is the third leading cause of cancer-related death worldwide. There are numerous possible factors that stimulate the procarcinogenic activity of important genes. These factors include genetic susceptibility expressed in a singlenucleotide polymorphism, various acquired mutations(chromosomal instability, microsatellite instability, somatic gene mutations, epigenetic alterations) and environmental circumstances(e.g., helicobcter pylori infection, EBV infection, diet, and smoking). Most of the aforementioned pathways overlap, and authors agree that a clear-cut pathway for GC may not exist. Thus, the categorization of carcinogenic events is complicated. Lately, it has been claimed that research on early-onset gastric carcinoma(EOGC) and hereditary GC may contribute towards unravelling some part of the mystery of the GC molecular pattern because young patients are less exposed to environmental carcinogens and because carcinogenesis in this setting may be more dependent on genetic factors. The comparison of various aspects that differ and coexist in EOGCs and conventional GCs might enable scientists to: distinguish which features in the pathway of gastric carcinogenesisare modifiable, discover specific GC markers and identify a specific target. This review provides a summary of the data published thus far concerning the molecular characteristics of GC and highlights the outstanding features of EOGC.