lncRNA XIST Interacts with Regulatory T Cells within the Tumor Microenvironment in Chronic Hepatitis B-Associated Hepatocellular Carcinoma

OBJECTIVE

Alterations in the expression of several long non-coding RNAs (lncRNAs) have been shown in chronic hepatitis B-associated hepatocellular carcinoma (CHB-HCC). Here, we aimed to investigate the association between the expression of inflammation-associated lncRNA X-inactive specific transcript (XIST) and the type of inflammatory cells within the tumor microenvironment.

MATERIAL AND METHODS

Twenty-one consecutive cirrhotic patients with CHB-HCC were included. XIST expression levels were investigated on formalin-fixed paraffin-embedded (FFPE) tumoral and peritumoral tissue samples by real-time polymerase chain reaction (RT-PCR). Immunohistochemical staining for CD3, CD4, CD8, CD25, CD163, CTLA4, and PD-1 were performed. The findings were statistically analyzed.

RESULTS

Of the 21 cases, 11 (52.4%) had tumoral and 10 (47.6%) had peritumoral XIST expression. No significant association was found between the degree of inflammation and XIST expression. The number of intratumoral CD3, CD4, CD8 and CD20 positive cells was higher in XIST-expressing tumors, albeit without statistical significance. Tumoral and peritumoral XIST expression tended to be more common in patients with tumoral and peritumoral CD4high inflammation. The number of intratumoral CD25 positive cells was significantly higher in XIST-expressing tumors (p=0.01). Tumoral XIST expression was significantly more common in intratumoral CD25high cases (p=0.04). Peritumoral XIST expression was also more common among patients with CD25high peritumoral inflammation, albeit without statistical significance (p=0.19).

CONCLUSION

lncRNA XIST is expressed in CHB-HCC and its expression is significantly associated with the inflammatory tumor microenvironment, particularly with the presence and number of CD25 (+) regulatory T cells. In vitro studies are needed to explore the detailed mechanism.

Peritumoral histopathologic findings in patients with chronic viral hepatitis-associated hepatocellular carcinoma

Data on peritumoral histopathologic findings in patients with hepatocellular carcinoma (HCC) is limited. In this retrospective study, we evaluated the peritumoral histopathologic changes in patients with chronic viral hepatitis (CVH)-associated HCC (CVH-HCC) and their prognostic value. 61 consecutive cirrhotic patients who underwent liver transplantation due to CVH-HCC were included. Histopathologic features within 1 cm distance of the tumor, and their association with clinicopathological characteristics and prognosis were evaluated. A random representative slide of cirrhotic parenchyma unrelated to invasive and/or dysplastic foci was also evaluated for the same histopathologic criteria. The majority (85%, n = 52) were male with a median age of 55 ± 6.38 (range, 39-67). The etiologic agent was only HBV in 90% (n = 55). The most common peritumoral findings were portal inflammation (100%; n = 61), ductular reaction (100%; n = 61) and sinusoidal dilatation (95%; n = 58). Macrovascular invasion was observed only in four cases (7%) with mild peritumoral portal inflammation. Neutrophilic infiltration of the peritumoral portal tracts (n = 18; 30%) was significantly associated with pT4 tumor stage, tumor grade, macrovascular invasion, and pretransplant therapy. Patients with moderate or severe peritumoral sinusoidal dilatation tended to have worse prognosis, albeit not significantly. Peritumoral ballooning degeneration was associated with multifocality, recurrence and recurrence-free survival in both uni- and multivariate analysis. Peritumoral histopathologic changes in CVH-HCC can be classified as: changes related to pathogenesis, changes indirectly affecting prognosis, and changes directly affecting prognosis. Peritumoral prominent ballooning degeneration may be a predictor of recurrence while portal neutrophilic infiltration and sinusoidal dilatation seem to indicate poor prognosis.

Tumoral and Parenchymal Morphological Assessment in Liver Metastases of Colorectal Carcinoma: Micrometastasis, Peritumoral Lymphocytes, Tumor Budding and Differentiation are Potential Prognostic Factors

Introduction: Various potential prognostic histopathologic factors for colorectal carcinoma liver metastasis have been proposed. However, there is still no consensus on pathological reporting of colorectal carcinoma liver metastasis resection materials. The aim of this study was to investigate the relation between selected tumoral and parenchymal histopathologic features and prognostic factors for better characterization and prognostic prediction of the patients with colorectal carcinoma liver metastasis. Methods: Hematoxylin-eosin stained slides from 100 patients who underwent hepatic resection were evaluated. Pathologic characteristics; including number of tumor nodules, largest tumor size, status of surgical margin, tumor distance to closest margin, tumor necrosis, the presence of tumor capsule, tumor differentiation, perineural and lymphovascular invasion, micrometastasis, tumor budding, peritumoral lymphocytic infiltrate and parenchymal features including steatosis, steatohepatitis, lobular inflammation, confluent necrosis, hepatocyte ballooning, portal inflammation were assessed. For 49 patients who were treated with preoperative chemotherapy, tumor regression grade and chemotherapy-related parenchymal changes such as sinusoidal damage, venous obstruction, nodular regenerative hyperplasia, steatosis and steatohepatitis were also evaluated. Results: The presence of lymphovascular invasion (p < 0.001), micrometastasis (p=0.004), absent or mild peritumoral lymphocytic infiltration (p =0.013), high tumor budding score (p=0.033) and moderate/poor differentiation (p=0.022) were significantly associated with shorter overall survival. Lymphovascular invasion (p < 0.001) was an independent predictor of mortality in multivariate analysis. Conclusions: We conclude that tumor differentiation, lymphovascular invasion, micrometastasis, peritumoral lymphocytic reaction and tumor budding score are potential prognostic histopathological features and candidates for inclusion in pathology reports of colorectal carcinoma liver metastasis resections.

The Site of Lymph Node Metastasis: A Significant Prognostic Factor in Pancreatic Ductal Adenocarcinoma

OBJECTIVE

While the presence and number of metastatic lymph nodes (LNs) are important prognostic factors for pancreatic ductal adenocarcinoma (PDAC), there is no recommendation to specify metastatic regional LN localization in the current staging system. The aim of this study was to evaluate the prognostic effect of regional metastatic LN localizations in PDAC.

MATERIAL AND METHOD

Metastatic sites of 101 consecutive PDAC patients who underwent pancreaticoduodenectomy were classified as peripancreatic, perigastric, hepatica communis, hepatoduodenal, and superior mesenteric artery. The frequency of metastasis in each region and the association between the presence of metastasis in each site and overall and disease-free survival were statistically analyzed.

RESULTS

Eighty cases (79.2%) had peripancreatic, 7 (6.9%) had perigastric, 6 (5.9%) had hepatica communis, 7 (6.9%) had hepatoduodenal, and 4 (4%) had superior mesenteric artery LN metastasis. The overall and disease-free survival values were significantly shorter in patients with hepatoduodenal LN metastasis (log rank; p= 0.001, p=0.017, respectively). The presence of metastatic superior mesenteric artery LN was significantly associated with shorter disease-free survival in univariate analysis (p=0.017). Hepatoduodenal LN metastasis was an independent predictor of mortality (p=0.005) in multivariate analysis.

CONCLUSION

The presence of hepatoduodenal LN metastasis is an independent poor prognostic factor for mortality. The presence of metastatic LN in the superior mesenteric artery region was significantly associated with shorter disease-free survival time, although not an independent predictor. We conclude that the metastatic regional LN sites, especially the hepatoduodenal region, have an impact on the prognosis, and should be included in synoptic pathology reports.

Reconsideration of Clinicopathologic Prognostic Factors in Pancreatic Neuroendocrine Tumors for Better Determination of Adverse Prognosis

The question of how successful we are in predicting pancreatic neuroendocrine tumors (panNET) with poor prognosis has not been fully answered yet. The aim of this study was to investigate the effects of clinicopathological features on prognosis and to determine their validity in prediction of prognosis and whether a better prognostic classification can be made. Fifty-six patients who underwent pancreatic resection for pancreatic neuroendocrine tumor were included. The associations between clinicopathological parameters and prognosis were evaluated statistically. Efficiencies of different thresholds for tumor size, mitotic count, and Ki67 proliferation index for prognosis prediction were compared. Vascular invasion was statistically associated with high tumor grade, advanced pT stage, and mortality rate. The presence of non-functional tumor, lymphatic invasion, and > 10 cm tumor size were significantly related to shorter overall survival. Advanced pT stage (pT3-4), > 5 cm tumor size, and high tumor grade (grades 2-3) were significantly associated with shorter disease-free survival. The mortality rate showed the strongest statistical significance with mitotic count when grouped as 1: < 2, 2: 2-10, and 3: > 10 mitosis/ 2 mm². The 10% threshold value for Ki67 index was more successful in predicting adverse prognosis. Among the morphologic variants, the ductulo-insular variant was the most promising to have positive prognostic value in our series, although no statistical significance was detected. In conclusion, threshold values of 5 cm and 10 cm for tumor size, 10% for Ki67 proliferation index, and 10/2 mm² for mitotic count and vascular and lymphatic invasion assessed separately are potential prognostic candidates for better stratification of panNETs.

A Nobel-Winning Scientist: Aziz Sancar and the Impact of his Work on the Molecular Pathology of Neoplastic Diseases

Aziz Sancar, Nobel Prize winning Turkish scientist, made several discoveries which had a major impact on molecular sciences, particularly disciplines that focus on carcinogenesis and cancer treatment, including molecular pathology. Cloning the photolyase gene, which was the initial step of his work on DNA repair mechanisms, discovery of the "Maxicell" method, explanation of the mechanism of nucleotide excision repair and transcription-coupled repair, discovery of "molecular matchmakers", and mapping human excision repair genes at single nucleotide resolution constitute his major research topics. Moreover, Sancar discovered the cryptochromes, the clock genes in humans, in 1998, and this discovery led to substantial progress in the understanding of the circadian clock and the introduction of the concept of "chrono-chemoterapy" for more effective therapy in cancer patients. This review focuses on Aziz Sancar's scientific studies and their reflections on molecular pathology of neoplastic diseases. While providing a new perspective for researchers working in the field of pathology and molecular pathology, this review is also an evidence of how basic sciences and clinical sciences complete each other.

The Predictive Ability of the Glasgow Prognostic Score and Variants in Both Deceased Donor and Living Donor Liver Transplantation for Hepatocellular Cancer

AIM

Liver transplantation (LT) is the most promising treatment method in hepatocellular cancer (HCC). Due to the shortage of organ donors and the possible risks associated with living donation, the selection of patients for LT is critical. The aim of this study is to investigate the predictive ability of the Glasgow Prognostic Score (GPS), modified GPS (mGPS), and hepatic GPS (hGPS) on prognoses in a patient group who underwent deceased donor LT (DDLT) or living-donor LT (LDLT) for HCC.

PATIENTS AND METHODS

This study includes 62 DDLT and 55 LDLT patients who underwent LT for HCC between 1998 and 2016 in a single center. The study endpoints were recurrence, 0- to 1-year mortality, 0- to 3-year mortality, mortality, and overall survival (OS).

RESULTS

The median follow-up time was 70.24 ± 48.47 months. GPS and hGPS positivity were found to be prognostic indicators of 0- to 3-year mortality and overall mortality in DDLT (P = .012, P = .006; P = .044 and P = .022 respectively). In the LDLT group, GPS was found to be effective in predicting 0- to 1-year and 0- to 3-year mortality (P = .045, P = .022 respectively); GPS and hGPS were also found to be effective in predicting overall mortality (P = .001 and P = .046 respectively). The OS was significantly longer in the GPS 0 group and hGPS 0 group compared to the GPS 1-2 and hGPS 1-2 group in both DDLT and LDLT.

CONCLUSION

The findings of this study and the literature indicate that using GPS and hGPS is appropriate in selecting patients with HCC who are candidates for LT.

Assessment of Effect of Intraperitoneal Tacrolimus on Liver Regeneration in Major (70%) Hepatectomy Model After Experimental Pringle Maneuver in Rats

AIM

Small-for-size grafts have become more important, especially in living donor liver transplants. The Pringle maneuver, used to reduce blood loss, and the immunosuppressive medications used to prevent graft rejection in liver transplants have different side effects on liver regeneration. We researched the effect of situations where tacrolimus and the Pringle maneuver were applied or not on liver regeneration in rats with partial hepatectomy.

MATERIAL AND METHODS

This study was completed with 35 Wistar Albino rats. The subjects were randomly divided into 5 groups: Group 1 had the abdomen opened and no other procedure was performed; Group 2 underwent a 70% hepatectomy; Group 3 underwent a 15-minute Pringle maneuver + 70% hepatectomy; Group 4 underwent a 70% hepatectomy + 5 days of 1 mg/kg/day intraperitoneal tacrolimus; and Group 5 underwent a 150 minute Pringle maneuver + 0% hepatectomy + 5 days of 1 mg/kg/day intraperitoneal tacrolimus. All rats were sacrificed on the seventh postoperative day, remaining liver tissue was weighed, and weight indices created. The remaining liver tissue was stained with phosphohistone H3 and the mitotic index calculated.

RESULTS

The groups that underwent the Pringle maneuver, 70% hepatectomy, and tacrolimus administration were compared with the control group in terms of mitotic index and weight index, but no statistically significant differences were identified.

CONCLUSION

Suppression of regeneration forms a risk after liver transplantation with small-volume grafts. As a result, research on the effect of tacrolimus combined with the Pringle maneuver is important, especially for transplantations using segmented liver grafts. In our study, we showed that the use of tacrolimus had no negative effect on liver regeneration.

The Effects of Darbepoetin on Peritoneal Fibrosis Induced by Chemical Peritonitis and on Peritoneal Tissue Mmp-2 and Timp-2 Levels in Rats

The aim of this study is to assess the influence of darbepoetin on the development of peritoneal fibrosis in rats induced by Chlorhexidine gluconate (0.1%) and ethanol (15%) and to determine the effect on peritoneal tissue levels of MMP–2 and TIMP–2, possible important factors in progression of peritoneal fibrosis. Twenty-four female Wistar albino rats were divided into three groups. The first group (CH group) received 3 ml/200g daily intraperitoneal injections of Chlorhexidine gluconate (0.1%) and ethanol (15%) dissolved in saline to induce chemical peritonitis; group 2 (ESA group) received 3 ml/200g daily injections of Chlorhexidine gluconate (0.1%) and ethanol (15%) dissolved in saline and also darbepoetin 12.5 microgr/ per kilogram/ day subcutaneously on the first and seventh days; group 3 (Control group) received intraperitoneal 0.9% saline (3 ml/200g/d) through the right lower quadrant by 21 gauge needle. The study duration was fourteen days. On the fifteenth day rats were sacrificed, parietal peritoneum samples were obtained from the left anterior abdominal wall. Pathological samples were examined using Hematoxyline & Eosin (HE) stains. The thickness, vasculpathy, and inflammation were determined by light microscopy. MMP-2 and TIMP-2 were studied immunohistochemically by monoclonal antibody staining. The activity of MMP-2 on peritoneal tissue was studied by gelatin zymography and TIMP–2 protein level was analysed by ELISA, biochemically. The decrease in thickness of parietal peritoneum in group ESA was statistically significant when compared to CH group (p<0.05). Inflammation scores, and vascularization score surfaces were not statistically different between these groups (p>0.05). Immunohistochemically, darbepoetin was shown to decrease MMP-2 expression on parietal peritoneum in CH group (p<0.05), but had no effect on TIMP-2 (p>0.05). Biochemically the ratio of active MMP–2 to proMMP–2 was more significantly increased in the ESA group than in the CH group (p<0.001), however, TIMP- 2 levels in both groups were decreased compared to the control group (p<0.05). Darbepoetin histopathologically reduced peritoneal fibrosis induced by Chlorhexidine gluconate. We can suggest that Darbepoetin does not cause peritoneal fibrosis and may prevent peritoneal fibrosis in rats possibly related to an effect on MMP-2 expression. Further research regarding the utility and dosage should be considered.

The Effects of Interferon α2b on Chemically-Induced Peritoneal Fibrosis and on Peritoneal Tissue MMP-2 and TIMP-2 Levels in Rats

This study investigated the effect of interferon α2b on chlorhexidine gluconate (CH)-induced peritoneal fibrosis (PF) in rats and assessed peritoneal tissue levels of metalloproteinase (MMP)-2 and tissue inhibitors of metalloproteinases (TIMP)-2. Wistar albino rats ( n = 8 per group) were treated as follows: control group, 3 ml/day of 0.9% saline intra-peritoneally for 28 days; CH group, 0.1% CH (200 g [3 ml]/day) in 15% ethanol and 0.9% saline intra-peritoneally for 28 days; CH + interferon (IFN) group, CH (as above) plus pegylated IFN-α2b 1.5 μg/kg per week subcutaneously on days 0, 7, 14, 21 and 28; IFN group, pegylated IFN-α2b (as above).

Parietal peritoneum samples were obtained from the left anterior abdominal wall after 35 days. Parietal thickness, degree of vascular proliferation and inflammation, and MMP-2 and TIMP-2 levels were determined. The mean peritoneal thicknesses of the control, CH, CH + IFN and IFN groups were 7.02 ± 3.89, 156.86 ± 29.13, 59.88 ± 22.1, 9.27 ± 2.03 μm, respectively. Pegylated IFN-α2b decreased CH-induced expression of MMP-2 in the parietal peritoneum, but had no effect on TIMP-2 levels. Further studies are needed to determine the optimal dosage and duration for pegylated IFN-α2b treatment.