Combined hepatocellular cholangiocarcinoma in hepatectomy specimens: A clinicopathologic analysis.

Background: Combined hepatocellular-cholangiocarcinoma (cHCC-CCA) is an uncommon form of primary liver carcinoma. It is heterogenous in terms of morphology, immunohistochemistry, radiology, and clinical features; making it a challenging entity for diagnosis. Aims: The purpose of the present study was to evaluate clinicopathological characteristics of patients with cHCC-CCA. Settings and Design: Retrospective observational study. Materials and Methods: The patients diagnosed with cHCC-CC were identified from hepatic surgical specimens and were evaluated. Statistical Analysis: Survival was estimated as per Kaplan-Meier method. Results: Out of six patients, five had undergone resection while one had liver transplant. Five were male and one was female and the mean age was 52 years. Tumor markers revealed raised serum alfa-fetoprotein and CA19.9 in four and three patients, respectively. Five of the liver specimens were cirrhotic. Diagnosis was predominantly based on tumor morphology. All cases were of Allen and Lisa type B and cHCC-CCA as per WHO (2019) classification. Stem cell features <5% were noted in two cases. Immunohistochemistry for programmed death 1/programmed death ligand 1 (PD1/PDL1) was negative in both the hepatocellular and cholangiocellular components in all six cases. Mismatch repair (MMR) protein expression was retained in two and deficient in four cases. The median follow-up after surgery was 21.3 months (range, 5-46.2 months). Five patients had intrahepatic and/or extrahepatic recurrence on follow-up after surgery. The median recurrence-free survival was estimated at 13.1 months (95% CI 5.67-20.6). Three patients had received salvage treatment. The median overall survival was estimated at 20 months (95% CI 0-45.3). Conclusions: The present study highlights the role of morphology in the diagnosis of cHCC-CCA. The choice of locoregional and/or systemic therapy after surgery may be individualized based on the clinicopathological characteristics.

A comparative histological analysis of early and late graft dysfunction in different time zones following living donor liver transplantation.

Background: Liver biopsy plays a crucial role in evaluating allograft dysfunction. Comprehensive analysis of the histological spectrum of complications, particularly rejection, in different time zones is lacking. Aim: To evaluate the histological spectrum of rejection, in four time zones, in a large Living donor liver transplant series. Patients and Methods: Retrospective analysis of 313 biopsies for the last 10 years of living donor liver transplantation (LDLT) recipients. 123 of which had rejection as diagnosis, were redistributed in four time zones [1-early (<3), 2-intermediate (3-6), 3 and 4-late (6-12 and > 12) months] and were assessed for sixteen histological parameters. Results: Biopsies in time zone 1 (26.5%), 2 (20.7%), 3 (24.6%), and 4 (28.1%)] were nearly equal. Multiple coexistent complications existed in 12% of the cases. Rejection diagnosed in time zone groups: 1 = 22 (17.9%), 2 = 27 (22%), 3 = 36 (29.3%), and 4 = 38 (30.9%). Portal inflammation mixed type (P < 0.000), portal vein (P = 0.001) and hepatic vein endothelialitis (P < 0.000), portal eosinophils (P = 0.001), and lymphocytic bile duct damage (P = 0.01) were most pronounced in group 1. Perivenulitis without hepatic vein endothelialitis was observed (P = 0.03) in groups 3, whereas bile duct atypia (P = 0.01) and duct loss (P < 0.000) were observed in group 4. Multiple episodes of rejection displayed significant association with central perivenulitis (P = 0.002) and bile duct loss (P < 0.001). Conclusions: Histological analysis in large series of LDLT recipients highlights the spectrum of complications in different time zones. Late acute and chronic rejection occurred as early as 3 months posttransplant. Central perivenulitis and bile duct atrophy were associated with repeated episodes of rejection and deterioration.

Rhino-orbito-cerebral mucormycosis: an epidemic in a pandemic.

Background: Opportunistic cases of rhino-orbito-cerebral mucormycosis (ROCM) have increased in India during the coronavirus disease 2019 (COVID-19) pandemic. Aim: To study laboratory parameters, histopathological features of sinus mucosal biopsies and exenterated orbit specimens, and clinical aspects of patients with ROCM. Materials and methods: Retrospective analysis of nasal and sinus debridement biopsies and orbital exenteration specimens of 30 patients was undertaken, along with analysis of laboratory parameters, clinical history of predisposing conditions, and medication history during COVID-19. Results: All patients were either in recovery following COVID-19 or had ongoing infection. Most patients were diabetic with increased glycosylated haemoglobin, and most patients received steroids and antibiotics for COVID-19. Thirty sinonasal mucosal debridement specimens from various sites, nine orbital exenteration specimens and one frontal decompression craniectomy specimen were examined. Mucor spp. were observed in necrotic tissue, and the presence of vessel and nerve invasion was documented. There were four deaths. Conclusion: ROCM is a life-threatening disease. A high index of suspicion with prompt aggressive surgical and medical management by a multi-disciplinary team can be life saving. Efforts to maintain an optimal glycaemic index is likely to be helpful in preventing ROCM. Judicious use of steroids is mandatory to control the collateral epidemic of ROCM in India.

Second-harmonic generation (SHG) microscopy and hepatic venous pressure gradient-based validation of a novel histological staging system for alcoholic hepatitis.

Alcoholic hepatitis (AH) lacks specific histological staging. A novel fibrosis staging that encompasses perisinusoidal fibrosis and cirrhosis sub-stages, substantiated by Hepatic venous pressure gradient (HVPG) and automated fibrosis quantification, is imperative. To correlate novel histological staging system of AH with second-harmonic generation microscopy (SHG)-based q-fibrosis, HVPG, and activated hepatic stellate cells (HSCs). Liver biopsies of AH (n = 175) were staged semi-quantitatively as F0, F1, F2, F3A and F3B and Laennec substages of cirrhosis 4A, 4B and 4C. Stages were correlated with SHG q-fibrosis parameters, HVPG and HSCs. Mean age 41.2 ± 9.4 years, 96.6% males, bilirubin 20.58 ± 8.0 mg/dl and Maddrey's discriminant function 78.9 ± 36.7 displayed advanced fibrosis in 98.6%. With increasing histological stages, an increase in q-fibrosis indices and mean HVPG (p < 0.0001) were recorded; stage 4C showed the most significant difference from other stages (p < 0.000). Stages 3A and 3B were comparable with the stages 4A and 4B, respectively, for q-fibrosis (p = 1) and HVPG (p = 1). HSCs (> 30%) were significantly higher in stage 3 (75%) compared with 4 (49%) and 2 (59%), p = 0.018. Overall agreement for histological staging was excellent for all stages (0.82). SHG quantified fibrosis and HVPG corroborates the novel histological staging of AH. Expansive PCF matches with collagen content and clinical severity to early sub-stages of cirrhosis. This highlights the need for an accurate quantification and inclusion of PCF as a separate stage. SHG-based quantification can be a useful adjunct to histological fibrosis staging systems.

An unusual case of hepatic lymphoma with multiple epithelial malignancies.

Primary hepatic mucosa-associated lymphoid tissue lymphoma (MALToma) is a rare entity. Its coexistence with other malignancies is even rarer. Only few case reports of its association with other malignancies mostly gastric and colon cancer have been published. We report a case of primary MALToma of liver in an unusual setting of dual solid malignancy.

Putative DNA modification methylase DR_C0020 of Deinococcus radiodurans is an atypical SAM dependent C-5 cytosine DNA methylase.

BACKGROUND: Control of cellular processes by epigenetic modification of cytosine in DNA is widespread among living organisms, but, is hitherto unknown in the extremely radioresistant microbe D. radiodurans. METHODS: C-5 methyl cytosines (m5C) were detected by immuno-blotting with m5C-specific antibody. Site of cytosine methylation by DR_C0020 encoded protein was investigated by bisulfite sequencing. The DR_C0020 knockout mutant (Δdcm), constructed by site directed mutagenesis, was assessed for effect on growth, radiation resistance and proteome. Proteins were identified by mass spectrometry. RESULTS: Methylated cytosines were detected in the D. radiodurans genome. The DR_C0020 encoded protein (Dcm, NCBI accession: WP_034351354.1), whose amino acid sequence resembles m4C methylases, was shown to be the lone SAM-dependent C-5 cytosine methyltransferase. Purified Dcm protein was found to methylate CpN sequence with a preference for methylation of two consecutive cytosines. The Δdcm strain completely lost m5C modification from its genome, had no effect on growth but became radiation sensitive. The Δdcm cells exhibited minor alterations in the abundance of several proteins involved primarily in protein homeostasis, oxidative stress defense, metabolism, etc. CONCLUSION: DR_C0020 encoded SAM-dependent methyltransferase Dcm is solely responsible for C-5cytosine methylation at CpN sites in the genome of D. radiodurans and regulates protein homeostasis under normal growth conditions. The protein is an unusual case of an amino methyltransferase that has evolved to producing m5C. GENERAL SIGNIFICANCE: Although, dispensable under optimal growth conditions, the presence of m5C may be important for recognition of parent strand and, thus, could contribute to the extraordinary DNA repair in D. radiodurans.

Epigenetic modulation upon exposure of lung fibroblasts to TiO2 and ZnO nanoparticles: alterations in DNA methylation.

Titanium dioxide (TiO2) and zinc oxide (ZnO) nanoparticles (NPs) are promising candidates for numerous applications in consumer products. This will lead to increased human exposure, thus posing a threat to human health. Both these types of NPs have been studied for their cell toxicity, immunotoxicity, and genotoxicity. However, effects of these NPs on epigenetic modulations have not been studied. Epigenetics is an important link in the genotype and phenotype modulation and misregulation can often lead to lifestyle diseases. In this study, we have evaluated the DNA methylation-based epigenetic changes upon exposure to various concentrations of NPs. The investigation was designed to evaluate global DNA methylation, estimating the corresponding methyltransferase activity and expression of Dnmt gene using lung fibroblast (MRC5) cell line as lungs are the primary route of entry and target of occupational exposure to TiO2 and ZnO NPs. Enzyme-linked immunosorbent assay-based immunochemical assay revealed dose-related decrease in global DNA methylation and DNA methyltransferase activity. We also found direct correlation between the concentration of NPs, global methylation levels, and expression levels of Dnmt1, 3A, and 3B genes upon exposure. This is the first study to investigate effect of exposure to TiO2 and ZnO on DNA methylation levels in MRC5 cells. Epigenetic processes are known to play an important role in reprogramming and adaptation ability of an organism and can have long-term consequences. We suggest that changes in DNA methylation can serve as good biomarkers for early exposure to NPs since they occur at concentrations well below the sublethal levels. Our results demonstrate a clear epigenetic alteration in response to metal oxide NPs and that this effect was dose-dependent.