Neutrophil Gelatinase-Associated Lipocalin for the Differentiation of Mucinous Pancreatic Cystic Lesions.

Undetermined pancreatic cystic lesion (PCL) differentiation benefits from endoscopic ultrasound (EUS) based on morphology and cyst fluid analysis, but room for new biomarkers exists. Our aim was to assess the intracystic and serum diagnostic value of neutrophil gelatinase-associated lipocalin (Ngal) and interleukin 1 beta (IL-1ß) for differentiation of PCLs. This prospective study included patients from one tertiary hospital, evaluated between April 2018 and May 2020. EUS fine-needle aspiration or pancreatic pseudocysts drainage was the source of PCL intracystic liquid. The final diagnosis was based on surgery or EUS results (morphology, cytology, glucose, and CEA-carcinoembryogenic antigen). The intracystic samples were tested for Ngal, IL-1ß, glucose, and CEA, and serum for Ngal and IL-1ß. We evaluated 63 cysts, 33 pseudocysts, and 30 non-inflammatory cysts. The diagnostic sensitivity and specificity for mucinous PCL was 70.8% and 92.3% for intracystic Ngal (cut-off: 500-800 ng/dL), without correlation with serum Ngal, no matter the inclusion of infected pseudocysts. After exclusion of infected pseudocysts, the sensitivity and specificity for glucose were 87% and 75%, respectively, and for CEA, they were 87.1%, and 96.8%, respectively. Intracystic Ngal shows promise in differentiating mucinous PCLs, but researchers need to conduct further studies to confirm its effectiveness. Intracystic IL-1ß and serum Ngal made no diagnostic contribution.

Microscopic Positive Margins in Gastric Adenocarcinoma Following Oncological Resection: Prognostic Factors and Long-Term Survival.

BACKGROUND: In the context of gastric cancer, surgical resection stands as the sole curative treatment. Central to influencing overall survival are the resection margins. This research aims to identify the factors influential in determining microscopically positive resection margins (R1) and to evaluate overall survival. METHODS: Our study encompassed 549 patients diagnosed with adenocarcinoma of the stomach who underwent curative-intent surgery between January 2011 and December 2021 in our Surgery Department. We investigated the incidence of positive margins (R1) and their impact on survival rates, as well as the determinants of R1. The standardization of R1 involved ensuring a margin distance of less than 1 mm from the tumor line to the margin. RESULTS: The incidence of R1 margins was 13.29% (73 patients). Among these, proximal R1 margins were observed in 29 patients (39.72%), while 49 cases (67.12%) presented circumferentially positive margins, with 20 cases (27.39%) exhibiting distally positive margins. Nineteen patients (26.02%) had two R1 margins, and 3 patients had all resection margins microscopically positive (4.10%). Factors such as tumor dimension, invasion of other organs, pT stage, pN stage, pL1 stage, pV1 stage, pPn stage, Lauren type, and tumoral grading demonstrated significance (p < 0.01) in the occurrence of positive R1 margins. CONCLUSION: Tumor dimension, invasion of other organs, pT stage, pN stage, pL1 stage, pV1 stage, pPn stage, Lauren type, and tumoral grading could be regarded as factors for predicting microscopically positive margins. Moreover, positive resection margins have a detrimental impact on overall survival.

Distinct Morphological and Molecular Profiles of NAFLD and NAFLD-associated HCC Revealed by Immunohistochemistry and MicroRNA Analysis.

BACKGROUND AND AIMS: Non-alcoholic fatty liver disease (NAFLD) is a common hepatic condition that can progress to hepatocellular carcinoma (HCC) in non-cirrhotic livers. To better understand the development of NAFLD-associated HCC, we performed an integrated morphological and molecular analysis to identify new insights that can improve the follow-up of NAFLD patients. METHODS: Our study included a cohort of 14 NAFLD-associated HCC and 41 NAFLD patients. We analyzed clinical parameters, a four-microRNA (miRNA) panel (miR-21-5p, miR-34a-5p, miR-130a-3p, and miR-155-3p) panel and their relationship with p53 and ß-catenin expression. RESULTS: In the study cohort, the NAFLD-associated HCC patients were predominantly male, older, had significantly altered hepatic function, and a higher incidence of hypertension, type 2 diabetes, and dyslipidemia. Morphologically, the NAFLD-HCC group had substantially higher steatosis, ballooning, and fibrosis grades than the NAFLD group. The ß-catenin expression was higher in both adjacent non-tumoral liver tissue (ANT) from NAFLD-associated HCC patients and in HCC tissue com-pared with NAFLD samples. The 4 miRNAs panel showed a dysregulated expression profile between NAFLD, ANT and HCC samples. CONCLUSIONS: This study provides important insights regarding the molecular mechanisms underlying HCC progression in NAFLD patients, allowing for the development of better screening strategies for the early detection of NAFLD-associated HCC.

The Role of Immunohistochemistry in the Differential Diagnosis between Intrahepatic Cholangiocarcinoma, Hepatocellular Carcinoma and Liver Metastasis, as Well as Its Prognostic Value.

Intrahepatic cholangiocarcinoma (iCCA) is the second most frequent primary hepatic malignant tumor, after hepatocellular carcinoma (HCC). Its incidence has risen worldwide, yet the only potentially curative treatment, surgical resection, is seldom applicable, and the median overall survival remains extremely low. So far, there are no personalized therapy regimens. This study investigated whether routine immunohistochemical stains have diagnostic and/or prognostic value in iCCA. Clinical, imaging, and pathology data were retrospectively gathered for patients diagnosed with iCCA, HCC, or liver metastases assessed using liver needle biopsies. Three study groups with an equal number of cases (n = 65) were formed. In the iCCA group, CK19, CA19-9, CK7, and CEA demonstrated the highest sensitivities (100%, 100%, 93.7%, and 82.6%, respectively). The most relevant stains used for diagnosing HCCs were Glypican 3, CD34 (sinusoidal pattern), and Hep Par 1, with corresponding sensitivities of 100%, 100%, and 98.2%. The immunohistochemical panels for diagnosing metastatic tumors were chosen after correlating the clinical data and morphologic H&E aspects. Moderate/intensely positive CK7 expression and absent/low amount of intratumoral immune cells were favorable prognostic factors and correlated with increased overall survival in both the univariate analysis and the multivariate regression adjusted for age, existence of cirrhosis, number of tumors, and tumor differentiation.

Enhanced diagnosis and prognosis of severe alcoholic hepatitis using novel metabolomic biomarkers.

AIM: Differentiating alcoholic hepatitis (AH) from acute decompensation of alcoholic cirrhosis (DC) is challenging, as the presentation and biochemistry are similar. We aimed to identify potential metabolomic biomarkers to differentiate between AH and DC, and to predict short-term mortality. METHODS: We included consecutive biopsy proven AH and DC patients, which were managed according to current guidelines and followed up until the end of the study. Untargeted metabolomics was assessed in all patients at baseline. Specific analyses were successively performed to identify potential biomarkers, which were further semi-quantitatively analysed against relevant clinical endpoints. RESULTS: Thirty-four patients with AH and 37 with DC were included. UHPLC-MS analysis identified 83 molecules potentially differentiating between AH and DC. C16-Sphinganine-1P (S1P) was the most increased, whereas Prostaglandin E2 (PGE2) was the most decreased. The PGE2/S1P ratio < 1.03 excellently discriminates between AH and DC: AUC 0.965 (p < 0.001), Se 90%, Sp 100%, PPV 0.91, NPV 1, and diagnostic accuracy 95%. This ratio is not influenced by the presence of infection (AUC 0.967 vs. 0.962), correlates with the Lille score at 7 days (r = -0.60; P = 0.022) and tends to be lower in corticosteroid non-responders as compared with patients who responded [0.85(±0.02) vs. 0.89(±0.05), P = 0.069]. Additionally, decreased ursodeoxycholic acid levels are correlated with MELD and Maddrey scores and predict mortality with a 77.27% accuracy (NPV = 100%). CONCLUSION: This study suggests the PGE2 (decreased)/S1P (increased) ratio as a biomarker to differentiate AH from DC. The study also finds that low levels of ursodeoxycholic acid could predict increased mortality in AH.

Tentative indicators of malaria in archaeological skeletal samples, a pilot study testing different methods.

OBJECTIVE: This study attempts to integrate multiple methods to investigate the presence of malaria in human skeletal samples from an archaeological context. MATERIALS: 33 well preserved human remains originating from a 17th-century archaeological site in southeastern Romania. METHODS: The human bone samples were analyzed using rapid diagnostic tests for malaria antigens and PCR amplification of Plasmodium falciparum apical membrane antigen 1. A preliminary test was performed to identify and briefly characterize the presence of hemozoin using a combination of TEM imaging and diffraction. RESULTS: The rapid diagnostic tests indicated that more than half of the examined samples were positive for Plasmodium antigens, but no traces of the parasites' genetic material were detected despite repeated attempts. The TEM images indicated that hemozoin might be a promising diagnostic marker of malaria in ancient bones. CONCLUSIONS: The indisputable identification of malaria in the analyzed archaeological population was not possible as none of the applied methodological strategies turned out to be straightforward. SIGNIFICANCE: This study reinforces the intricacy and limitations of unequivocally identifying malaria in past populations and sets the stage for future studies on such life-threatening infectious disease in a geographical space, which is currently underrepresented in the bioarchaeological literature. LIMITATIONS: The low sample size and the lack of consistency across all assays hindered understanding the role of malaria in the studied population. SUGGESTIONS FOR FURTHER RESEARCH: Further thorough multidisciplinary approaches on malaria detection in ancient settlements would be appropriate to inform our knowledge of its origins, frequency, and pathogen changes over centuries.

PD-L1 expression on immune cells, but not on tumor cells, is a favorable prognostic factor for patients with intrahepatic cholangiocarcinoma.

Cholangiocarcinoma, the second most common liver malignancy, after hepatocarcinoma is highly aggressive and usually diagnosed in advanced cases. In the era of personalized medicine, targeted therapy protocols are limited for cholangiocarcinoma and the only potential curative treatment, surgical resection, is seldom applicable.This retrospective study included all cases with pathology-confirmed intrahepatic cholangiocarcinoma admitted in a tertiary healthcare facility during a 10-year timeframe. Clinical information, laboratory values, imaging studies, and survival data were retrieved, and PD-L1 immunostaining was performed on representative pathology slides, for each case. From the total of 136 included cases (49 surgical resections and 87 liver biopsies), 38.97% showed PD-L1 positivity on tumoral cells, 34.8% on tumor infiltrating immune cells, 10.11% on epithelial cells within the peritumoral area and 15.95% on immune cells from the peritumoral area. Overall survival was significantly higher in the first two scenarios. However, after adjusting for age, tumor number, tumor size, and tumor differentiation in a multivariate analysis, only PD-L1 positivity on tumor infiltrating immune cells remained a favorable prognostic for survival. High immune cell counts also correlated with increased overall survival.Our study demonstrated that PD-1/PD-L1 checkpoint pathway in the microenvironment of intrahepatic cholangiocarcinoma bears prognostic significance. PD-L1 expression on immune cells, in both resection and biopsy specimens, might be a strong independent predictor for a favorable outcome.

The Implications of Noncoding RNAs in the Evolution and Progression of Nonalcoholic Fatty Liver Disease (NAFLD)-Related HCC.

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent liver pathology worldwide. Meanwhile, liver cancer represents the sixth most common malignancy, with hepatocellular carcinoma (HCC) as the primary, most prevalent subtype. Due to the rising incidence of metabolic disorders, NAFLD has become one of the main contributing factors to HCC development. However, although NAFLD might account for about a fourth of HCC cases, there is currently a significant gap in HCC surveillance protocols regarding noncirrhotic NAFLD patients, so the majority of NAFLD-related HCC cases were diagnosed in late stages when survival chances are minimal. However, in the past decade, the focus in cancer genomics has shifted towards the noncoding part of the genome, especially on the microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), which have proved to be involved in the regulation of several malignant processes. This review aims to summarize the current knowledge regarding some of the main dysregulated, noncoding RNAs (ncRNAs) and their implications for NAFLD and HCC development. A central focus of the review is on miRNA and lncRNAs that can influence the progression of NAFLD towards HCC and how they can be used as potential screening tools and future therapeutic targets.

Clinical Utility of the Contrast-Enhanced Endoscopic Ultrasound Guided Fine Needle Aspiration in the Diagnosis of Pancreatic Cyst.

Endoscopic ultrasound fine needle aspiration (EUS-FNA) cytology from an intracystic fluid is useful in the differentiation of pancreatic cysts, with low sensitivity, which increases when the solid component is targeted. The clinical utility of contrast-enhanced guided EUS-FNA (CH-EUS-FNA) in the solid component is not known. We aimed to assess the diagnostic value of CH-EUS-FNA in enhanced mural nodules and discrimination between different cysts using contrast-enhanced endoscopic ultrasound (CH-EUS). The prospective study recruited patients with pancreatic cysts with an unclear diagnosis. The CH-EUS was followed by CH-EUS-FNA. The final diagnosis was based on surgery or the correlation between clinical history, cross-sectional imaging, echoendoscopic morphology, cystic fluid analysis, and follow-up. Fifty-eight patients with pancreatic cysts were evaluated. The mucinous cysts had wall arterial enhancement more often than non- mucinous cysts (p < 0.0001), with 90.2% sensitivity and 70.6% specificity. The CH-EUS-FNA from cystic fluid and mural nodules identified mucinous cysts and malignancy with 82.4% and 84.2% sensitivity and 92% and 100% specificity. Twenty-one cysts had solid components, but only 13 were enhanced mural nodules on EUS assessment with conclusive cytology in all cases and malignancy in 76.9%. Contrast-enhanced endoscopic ultrasound should be completed in all PCN with solid components in order to avoid unnecessary EUS-FNA and to guide FNA for the identification of malignant cysts.

Endoscopic Ultrasound-Guided Fine-Needle Biopsy versus Fine-Needle Aspiration in the Diagnosis of Focal Liver Lesions: Prospective Head-to-Head Comparison.

Endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) or fine-needle aspiration (EUS-FNA) from focal liver lesions are indicated in selected cases, but there has been no previous comparison of needle types of the same size. The aim of our study was to compare the histologic diagnostic accuracy and adequacy of cores obtained with EUS-FNB needles in contrast to those obtained with FNA needles in focal liver lesions. This prospective one-center study included patients with left lobe hepatic focal lesions with contraindications for percutaneous liver biopsy or need for EUS for concomitant lesions. Each patient had one pass of 22G EUS-FNB (Franseen) needle and one pass of 22G EUS-FNA in a crossover manner, without macroscopic on-site evaluation. Each sample was analyzed separately for histologic adequacy and diagnosis. The final diagnosis was based on histology results or on imaging follow-up in the case of negative biopsies. The EUS-FNB samples (n = 30) were found to be more adequate for histologic analysis, with more cellularity and longer tissue aggregates than the EUS-FNA samples (n = 30). The accuracy of EUS-FNB was 100%, whereas that of EUS-FNA was 86.7% (p = 0.039). No post-procedure complications were noted. The 22G EUS-FNB needle proved superior to 22G EUS-FNA in terms of tissue acquisition diagnostic accuracy and histologic adequacy in focal liver lesions.

Pancreatic Adenocarcinoma Associated to Intraductal Papillary Mucinous Neoplasia: Histopathological Particularities and Clinical Implications.

Background: Pancreatic ductal adenocarcinoma (PDAC) is the most common pancreatic tumor, known for an aggressive evolution. Intraductal papillary mucinous neoplasm (IPMN) is a rare pancreatic tumor, considered a premalignant lesion with the possibility of carcinogenesis towards PDAC. The clinical, surgical and histopathological particularities of the association between PDAC and IPMN are yet unknown, further research being needed. Methods: We have conducted a retrospective descriptive study, on a nine-year period (2012-2020), with the aim of comparing the characteristics of patients that underwent curative surgical interventions for solitary PDAC and PDAC associated to IPMN. Results: Fifteen patients with PDAC associated with IPMN (Group 1) and 386 patients with solitary PDAC (Group 2) were included in our study. Group 1 had a younger average age (61.8 years) compared to Group 2 (63.89 years). Total pancreatectomy was more frequently performed for Group 1 than Group 2 (33.33% vs 12.43%). Group 1 had a higher percentage of cases with positive perineural, perilymphatic and perivascular invasion. Group 1 registered a worse overall survival, as well as a worse short-time survival compared to Group 2. Conclusions: PDAC associated to IPMN registers distinct epidemiological, clinical and histopathological characteristics compared to solitary PDAC.

CT-Based Radiomic Analysis May Predict Bacteriological Features of Infected Intraperitoneal Fluid Collections after Gastric Cancer Surgery.

The ability of texture analysis (TA) features to discriminate between different types of infected fluid collections, as seen on computed tomography (CT) images, has never been investigated. The study comprised forty patients who had pathological post-operative fluid collections following gastric cancer surgery and underwent CT scans. Patients were separated into six groups based on advanced microbiological analysis of the fluid: mono bacterial (n = 16)/multiple-bacterial (n = 24)/fungal (n = 14)/non-fungal (n = 26) infection and drug susceptibility tests into: multiple drug-resistance bacteria (n = 23) and non-resistant bacteria (n = 17). Dedicated software was used to extract the collections' TA parameters. The parameters obtained were used to compare fungal and non-fungal infections, mono-bacterial and multiple-bacterial infections, and multiresistant and non-resistant infections. Univariate and receiver operating characteristic analyses and the calculation of sensitivity (Se) and specificity (Sp) were used to identify the best-suited parameters for distinguishing between the selected groups. TA parameters were able to differentiate between fungal and non-fungal collections (ATeta3, p = 0.02; 55% Se, 100% Sp), mono and multiple-bacterial (CN2D6AngScMom, p = 0.03); 80% Se, 64.29% Sp) and between multiresistant and non-multiresistant collections (CN2D6Contrast, p = 0.04; 100% Se, 50% Sp). CT-based TA can statistically differentiate between different types of infected fluid collections. However, it is unclear which of the fluids' micro or macroscopic features are reflected by the texture parameters. In addition, this cohort is used as a training cohort for the imaging algorithm, with further validation cohorts being required to confirm the changes detected by the algorithm.

Computed Tomography for the Diagnosis of Intraperitoneal Infected Fluid Collections after Surgery for Gastric Cancer. Role of Texture Analysis.

BACKGROUND AND AIMS: Several computed tomographic (CT) imaging features have been proposed to describe the infection of postoperative abdominal fluid collections; however, these features are vague, and there is a significant overlap between infected and non-infected collections. We assessed the role of textural parameters as additional diagnostic tools for distinguishing between infected and non-infected peritoneal collections in patients operated for gastric cancer. METHODS: From 527 patients operated for gastric cancer, we retrospectively selected 82 cases with intraperitoneal collections who underwent CT exams. The fluid component was analyzed through a novel method (texture analysis); different patterns of pixel intensity and distribution were extracted and processed through a dedicated software (MaZda). A univariate analysis comparing the parameters of texture analysis between the two groups was performed. Afterwards, a multivariate analysis was performed for the univariate statistically significant parameters. RESULTS: The study included 82 patients with bacteriologically verified infected (n=40) and noninfected (n=42) intraperitoneal effusions. The univariate analysis evidenced statistically significant differences between all the parameters involved. The multivariate analysis highlighted 10 parameters as being statistically significant, adjusted to Bonferroni correction. CONCLUSIONS: Our evidence supports the fact that textural analysis can be used as a complementary diagnostic tool for the detection of infected fluid collections after gastric cancer surgery. Further studies are required to validate the accuracy of this method.

Cellular and Molecular Profiling of Tumor Microenvironment and Early-Stage Lung Cancer.

Lung cancers are broadly divided into two categories: non-small-cell lung carcinoma (NSCLC), which accounts for 80-85% of all cancer cases, and small-cell lung carcinoma (SCLC), which covers the remaining 10-15%. Recent advances in cancer biology and genomics research have allowed an in-depth characterization of lung cancers that have revealed new therapy targets (EGFR, ALK, ROS, and KRAS mutations) and have the potential of revealing even more biomarkers for diagnostic, prognostic, and targeted therapies. A new source of biomarkers is represented by non-coding RNAs, especially microRNAs (miRNAs). MiRNAs are short non-coding RNA sequences that have essential regulatory roles in multiple cancers. Therefore, we aim to investigate the tumor microenvironment (TME) and miRNA tumor profile in a subset of 51 early-stage lung cancer samples (T1 and T2) to better understand early tumor and TME organization and molecular dysregulation. We analyzed the immunohistochemistry expression of CD4 and CD8 as markers of the main TME immune populations, E-cadherin to evaluate early-stage epithelial-to-mesenchymal transition (EMT), and p53, the main altered tumor suppressor gene in lung cancer. Starting from these 4 markers, we identified and validated 4 miRNAs that target TP53 and regulate EMT that can be further investigated as potential early-stage lung cancer biomarkers.

Contrast enhanced endoscopic ultrasound in the diagnosis of pancreatic metastases.

AIM: Less than 5% of pancreatic masses represent metastases and differentiation from primitive tumors using endo-scopic ultrasound (EUS) is difficult. The aim of our work was to assess the diagnostic value of contrast-enhanced harmonic endoscopic ultrasound (CH-EUS) for pancreatic metastases. MATERIAL AND METHODS: We retrospectively analyzed patients with pancreatic metastasis identified during a 8 year period in a tertiary medical center. RESULTS: We included in the study 20 patients evaluated with EUS and CH-EUS. The primary tumor was localized in the kidney (6 cases), lung (5 cases), colon (3 cases), skin (2 patients) and stomach, breast, ovary and liver (1 patient each). Only 11 patients (55%) (kidney, lung, liver, ovary or skin metastases), presented hypervascularity at EUS and arterial hyperenhancement on CH-EUS, with similar diag-nostic value. All renal metastases were hyperenhanced (the negative predictive value 100%) and the stomach, colon and ovary metastases were hypoenhanced. The fast wash-out of contrast substance was encountered in all cases or renal, pulmonary and digestive metastases, but with 53.3-64.3% specificity for the different origin of pancreatic metastases. CONCLUSIONS: The vascularity assessments on conventional EUS or CH-EUS are similar for pancreatic metastases of different origin. EUS tissue acquisition remains mandatory for the diagnosis.

The added value of CEUS and ultrasound-guided biopsy in diagnosing an aggressive desmoplastic small round cell tumour of peritoneum in a young male. A case report.

Desmoplastic small round cell tumour (DSRCT) is a rare and highly aggressive mesenchymal neoplasm with poor prognosis that develops in male adolescents and young adults. We report the case of a 32-year-old male admitted with abdominal distension and ascites. An ultrasonography (US) scan showed multiple peritoneal masses with large ascites. The dominant mass had a hypervascular homogenous aspect at contrast-enhanced ultrasound with wash-out in the venous phase. Thoracoabdominal CT, performed for staging the disease, confirmed the US aspect. The US-guided percutaneous biopsy revealed DSRCT of the peritoneum. Chemotherapy was then started with minimal clinical improvement, increase in tumoral burden and death after three months. US and US-guided biopsy played an essential role in diagnosing this case. The aggressive course of the disease and seeding at paracentesis sites are the particularities of the presented case.

Direct Comparison of Elastography Endoscopic Ultrasound Fine-Needle Aspiration and B-Mode Endoscopic Ultrasound Fine-Needle Aspiration in Diagnosing Solid Pancreatic Lesions.

Elastography endoscopic ultrasound (E-EUS) has been proved to be a valuable supplement to endoscopic ultrasound fine-needle aspiration (EUS-FNA) in differentiating solid pancreatic lesions, but the improvement of EUS-FNA guided during E-EUS has not been proven. Our study aimed to evaluate whether E-EUS fine-needle aspiration (E-EUS-FNA) was superior to B-mode EUS-FNA for the diagnosis of solid pancreatic masses and whether the diagnostic rate was affected by specific factors. Our prospective study was conducted between 2019-2020 by recruiting patients with solid pancreatic masses. E-EUS examination was followed by one pass of E-EUS-FNA towards the blue part of the lesion and a second pass of EUS-FNA. The final diagnosis was based on surgery, E-EUS-FNA or EUS-FNA results, or a 12-month follow-up. Sixty patients with solid pancreatic lesions were evaluated. The sensitivity, specificity, and accuracy for diagnosing malignancy using E-EUS-FNA and EUS-FNA were 89.5%, 100%, 90%, 93%, 100%, and 93.3%, respectively, but the differences were not significant. Neither mass location nor the lesion size influenced the results. The lengths of the core obtained during E-EUS-FNA and EUS-FNA were similar. E-EUS-FNA in solid pancreatic lesions was not superior to B-mode EUS-FNA.

Focus on organoids: cooperation and interconnection with extracellular vesicles - Is this the future of in vitro modeling?

Organoids are simplified in vitro model systems of organs that are used for modeling tissue development and disease, drug screening, cell therapy, and personalized medicine. Despite considerable success in the design of organoids, challenges remain in achieving real-life applications. Organoids serve as unique and organized groups of micro physiological systems that are capable of self-renewal and self-organization. Moreover, they exhibit similar organ functionality(ies) as that of tissue(s) of origin. Organoids can be designed from adult stem cells, induced pluripotent stem cells, or embryonic stem cells. They consist of most of the important cell types of the desired tissue/organ along with the topology and cell-cell interactions that are highly similar to those of an in vivo tissue/organ. Organoids have gained interest in human biomedical research, as they demonstrate high promise for use in basic, translational, and applied research. As in vitro models, organoids offer significant opportunities for reducing the reliance and use of experimental animals. In this review, we will provide an overview of organoids, as well as those intercellular communications mediated by extracellular vesicles (EVs), and discuss the importance of organoids in modeling a tumor immune microenvironment (TIME). Organoids can also be exploited to develop a better understanding of intercellular communications mediated by EVs. Also, organoids are useful in mimicking TIME, thereby offering a better-controlled environment for studying various associated biological processes and immune cell types involved in tumor immunity, such as T-cells, macrophages, dendritic cells, and myeloid-derived suppressor cells, among others.

Analysis of the MLH1, MLH2, MLH6, PMS2 genes and their correlations with clinical data in rectal mucinous adenocarcinoma.

BACKGROUND: Microsatellites are short repeated DNA sequences normally found in the human genome. Following specific mutations, microsatellites can vary in the number of repeats thus making the DNA unstable. Microsatellite instability (MSI) is responsible for approximately 20% of rectal cancers, while the remaining 80% are caused by chromosomal instability. One of the following genes, MLH1, MLH2, MLH 6, and PMS2, is inactivated, leading to MSI colorectal cancers. AIM: This study aimed to analyze the expression of some MMR system genes presenting mutations in mucinous rectal cancer and their correlations with clinical data. METHODS: A retrospective study was performed on patients with rectal mucinous adenocarcinoma who underwent surgery between January 2000 and January 2017. We collected a total of 42 patients and analyzed the demographic data, histopathological results and MMR system genes mentioned above. RESULTS: Almost 93% of the cases analyzed had MSI-H and only 7% were MSI-L. For MLH1, 50% of stage T2 and 50% of stage T4 had weak expression, while in stage T3, 42.50% had moderate expression. Regarding the N stage, we found that 66.67% of the patients with moderate gene expression (2+) were N2, while 42% of the patients with weak expression were N0. For MSH2, the majority of patients with strong gene expression were in stage T3 (27%). Weak expression was found in 50% of the patients in stage T2, 35% of the patients in stage T3, and 33.3% in T4. In 44.44% of the weak expression was N2, while for strong expression, there was an equivalent percentage of 33.33% in stages N1 and N2. Describing the MSH6 gene, we found that the most heterogeneous results were in stage T3. Weak expression was observed in 38.46% of the patients, while moderate and strong expression was observed in 30.77% and 11.54% respectively. Analysis of PMS2 revealed that 66.67% of the patients in stage T4 had a weak expression of the gene, while the same expression was found in 38.46% of the patients in stage T3. A total of 23.08% of patients in stage T3 had strong gene expression. We also analyzed the overall gene expression. Thus, we found that three patients (7.14%) had only 1, three genes were expressed, nine (21.42%) had two genes and the remaining 27 patients had all 4. The 1-year survival rate in the analyzed lot was 75%, decreasing to 60% in the second year and 35% in the 3rd. There were no statistically significant differences in survival data between the stages or gene expression. CONCLUSIONS: Our study showed no statistical difference regarding the survival on different gene expression or staging, consistent with studies that found that mucin expression does not have a significant impact on local recurrence, nor does it affect nodal down staging. KEY WORDS: Mucinous adenocarcinoma, Microsatelites instability.