Giuseppe Giuffrè

Microsatellite analysis of hereditary nonpolyposis colorectal cancer-associated colorectal adenomas by laser-assisted microdissection: Correlation with mismatch repair protein expression provides new insights in early steps of tumorigenesis

Although microsatellite instability (MSI) testing is a useful tool for molecular screening of hereditary nonpolyposis colorectal cancer (HNPCC) carcinomas, conflicting results have been obtained in colorectal adenomas. This might result from different techniques of tissue sampling and MSI analysis. Alternatively, some HNPCC-associated adenomas may follow a molecular route that differs from the MSI pathway. In the present study we examined the MSI status of 18 adenomas from 17 HNPCC patients by comparing manual adenoma dissection under gross visual control with laser microdissection of single adenoma crypts. After manual gross dissection, 50% (9 of 18) and 11.1% (2 of 18) of the adenomas displayed high-level (MSI-H) and low-level (MSI-L) MSI, respectively. The same set of adenomas split into 83.3% (15 of 18) MSI-H and 5.6% (1 of 18) MSI-L after laser microdissection. The expression pattern of mismatch repair (MMR) proteins showed a higher concordance rate with the MSI status in laser-dissected (94%) than gross-dissected (47%) adenomas. Whereas two adenomas remained microsatellite stable (MSS) and MMR proficient even after laser-assisted dissection, two MSI-H cases showed either rare instabilities at coding microsatellites or intratumoral heterogeneity of MSI with and without MSH2 expression. This suggests that in some adenomas development of MMR dysfunction occurs stepwise with MSI, arising before complete loss of MMR gene expression, whereas other HNPCC-associated adenomas might develop independently of MMR deficiency.

Immunohistochemical expression of metallothionein in normal human colorectal mucosa, in adenomas and in adenocarcinomas and their associated metastases

The immunohistochemial distribution pattern of metallothionein, a low molecular weight protein with strong affinity for divalent heavy metal ions, has been investigated in normal and neoplastic conditions of the large bowel. Utilizing a monoclonal mouse antibody the following formalin‐fixed paraffin‐embedded surgical or biopsy samples were studied: tubulo‐villous adenomas (8 cases); adenocarcinomas with various degree of differentiation (85), nine of which were mucinous‐type; synchronous tubular or tubulo‐villous adenomas separate from carcinomas (30); transitional mucosa (45); metastases in lymph nodes (43); and distant metastases (45). Twenty biopsies from the right and left colon of 10 patients affected by irritable bowel syndrome were also analyzed. Normal colonic mucosa as well as transitional mucosa showed metallothionein immunopositivity in enterocytes at the luminal surface and crypts. Evident nuclear and cytoplasmic staining was encountered in tubulo‐villous adenomas; the same reactivity was noted in the basal glandular component of colorectal carcinomas‐synchronous adenomas, while less intense staining was noted in the apical villous portions. A variable metallothionein immunostaining was observed in adenocarcinomas (62.3%), in lymph node (55.8%) and distant hepatic (17.2%) and omental (43.8%) metastases, although it was not always concordant with that reported in the corresponding primary tumour. Whether the metallothionein positivity observed in normal and neoplastic cells is the result of expression of a stable form of the protein or an accumulation in the nucleus and cytoplasm remains to be clarified.

HER2 status in unusual histological variants of gastric adenocarcinomas

Aim To investigate HER2 status in a cohort of 109 gastric adenocarcinomas also including unusual variants, such as 14 hepatoid (HAS) and 9 mitochondrion-rich (MRC), characterised by an opposing clinical behaviour. Methods and Results Using HercepTest (DAKO) and FISH test (pharmDx DAKO), HER2 overexpression/amplification was encountered in 23 of 109 (21.10%) of all gastric adenocarcinomas. A progressive increase in HER2 overexpression was observed moving from the poorly cohesive histotype to MRC, tubular adenocarcinomas and HAS. A statistically significant difference was found between poorly cohesive carcinomas and the others; a similar significant difference was encountered between HAS and all other variants of adenocarcinoma. HER2 overexpression was significantly associated with high grade, advanced stage, high Ki-67 labelling index value and death from gastric cancer. Multivariate analysis identified HER2 overexpression as an independent unfavourable prognostic variable for adenocarcinomas as a whole and also for the HAS variant. Conclusions Trastuzumab has been confirmed as an additional useful therapeutic standard option for patients with HER2-positive advanced gastric cancers, and also in aggressive variants of adenocarcinomas such as HAS.

The expression of adiponectin receptors Adipo-R1 and Adipo-R2 is associated with an intestinal histotype and longer survival in gastric carcinoma

Background: Adiponectin (ApN) is a 30 kDa adipocytokine which mediates an antineoplastic effect after binding to its receptors, Adipo-R1 and Adipo-R2. The expression of these receptors has been documented in gastric cancer (GC) cell lines, but only a few data exist on their expression in GC neoplastic tissue. Aim: To investigate the expression of Adipo-R1 and Adipo-R2 in a series of surgically resected GCs and to assess its association with various tumour clinicopathological characteristics as well as with patient survival. Methods: Forty-nine surgically resected GCs were submitted to immunohistochemical assays for Adipo-R1, Adipo-R2 and ApN. Results: Adipo-R1 and Adipo-R2 immunoexpression was found in 22/49 GCs and in intestinal metaplasia areas near the tumours, whereas only slight immunoreactivity for these proteins was found in adjacent normal gastric epithelium. No ApN expression was encountered in any of the cases analysed. Adipo-R1/Adipo-R2 expression was significantly associated with an intestinal histotype of the tumours and with longer overall survival of the patients. Conclusions: Intestinal-type GCs often express Adipo-R1/R2 in association with a better prognosis. The presence of these receptors could be exploited for novel anticancer therapies based on ApN addition in GC.

Less frequently mutated genes in colorectal cancer: evidences from next-generation sequencing of 653 routine cases.

Aims The incidence of RAS/RAF/PI3KA and TP53 gene mutations in colorectal cancer (CRC) is well established. Less information, however, is available on other components of the CRC genomic landscape, which are potential CRC prognostic/predictive markers. Methods Following a previous validation study, ion-semiconductor next-generation sequencing (NGS) was employed to process 653 routine CRC samples by a multiplex PCR targeting 91 hotspot regions in 22 CRC significant genes. Results A total of 796 somatic mutations in 499 (76.4%) tumours were detected. Besides RAS/RAF/PI3KA and TP53, other 12 genes showed at least one mutation including FBXW7 (6%), PTEN (2.8%), SMAD4 (2.1%), EGFR (1.2%), CTNNB1 (1.1%), AKT1 (0.9%), STK11 (0.8%), ERBB2 (0.6%), ERBB4 (0.6%), ALK (0.2%), MAP2K1 (0.2%) and NOTCH1 (0.2%). Conclusions In a routine diagnostic setting, NGS had the potential to generate robust and comprehensive genetic information also including less frequently mutated genes potentially relevant for prognostic assessments or for actionable treatments.

Immunocytochemical detection of DNA topoisomerase type II in primary breast carcinomas: Correlation with clinico-pathological features

DNA topoisomerase type II (DT-II) is a major component of interphase nuclear matrix fractions, present in S-phase of the cell cycle. A series of 80 carcinomatous breast surgical samples was evaluated by immunohistochemistry, using a polyclonal antibody in a comparison with Ki-67 antiserum. A correlation with clinico-pathological data was also performed. Infiltrating ductal and lobular carcinomas constantly express DT-II with varying intensity of nuclear staining; a similar immunohistochemical pattern is observed with Ki-67. A frequent co-expression of DT-II and Ki-67 is encountered with double immunostaining; accordingly to these data, a linear relationship is evident when linear regression is employed. In addition, significant relationships between DT-II values and tumour size, histological grade and node involvement are shown, while an inverse correlation is appreciable between DT-II and oestrogen receptors and progesterone receptors. DT-II may be considered to be an additional operational marker for the proliferating fraction of cells in breast carcinomas.

HER2 status in advanced gastric carcinoma: A retrospective multicentric analysis from Sicily.

According to the ToGA trial, HER2 has been shown to be predictive for the success of treatment with trastuzumab in advanced gastric cancer (AGC). A number of studies have analyzed HER-2/neu overexpression in gastric carcinoma and identified the rate of HER2 positivity to be markedly varied. To date, the prevalence of HER2 overexpression in Sicilian people with AGC is unknown. Therefore, in the present study, a retrospective immunohistochemical analysis of HER2 was performed in a cohort of 304 AGC samples that were obtained from the archives of 10 Sicilian anatomopathological diagnostic units in order to verify the positive rate of HER2-positive cases. Furthermore, the characteristics of histotype, grade, stage and Ki-67 expression were also analyzed. HER2 overexpression was encountered in 17.43% of all the gastric adenocarcinomas, which was consistent with the results that have been reported elsewhere in the literature. A progressive increase in HER2 overexpression was observed, from the poorly cohesive histotype to the tubular adenocarcinomas and gastric hepatoid adenocarcinomas. HER2 overexpression was significantly associated with a high grade, advanced stage and high Ki-67 labeling index. Further investigations performed jointly by pathologists and oncologists within the geographical area of the present study should confirm that the association of trastuzumab with chemotherapy results in an improvement of survival in patients with AGC.

AgNOR quantity as a prognostic tool in hyperplastic and neoplastic parathyroid glands

Abstract Prediction of evolution of secondary hyperplasia and tumours of the parathyroid glands is still a problem in histopathology. To assess whether the quantity of silver-stained nucleolar organiser region (AgNOR) proteins might be used as a prognostic tool in parathyroid pathology, a standardised AgNOR analysis has been performed on 19 cases of parathyroid hyperplasia caused by secondary hyperparathyroidism (PH), 8 cases of adenoma (PA) and 10 cases of carcinoma (PC). Clinico-pathological data and follow-up information were available. On formalin-fixed and paraffin-embedded sections, the visualisation and quantification of AgNORs were achieved according to the 1995 guidelines of the Committee on AgNOR Quantification. Then, the mean area (square micrometres) of AgNORs per nucleus (NORA) was evaluated by means of an image analyser and specific softwares. After testing the normal distribution of NORA values, statistical parametric tests were utilised; Kaplan-Meier and Cox multivariate analyses were also performed. In parathyroid lesions, a progressive increase of mean NORA values was observed from PH (2.895 µm2; SE 0.171) through PA (3.638 µm2; SE 0.125) to PC (4.701 µm2; SE 0.179); these differences were highly significant (P<0.001), although some degree of overlap was found among single NORA values. A significantly higher mean NORA value was revealed in PC with distant metastases than was noted in cases with no current clinical evidence of disease progression. Furthermore, a significantly (P<0.001) higher mean NORA value was encountered in the group of PH with recurrences (3.600 µm2; SE 0.106) than in nonrecurrent PH (2.261 µm2; SE 0.087). Multivariate analyses indicated that the NORA value was an independent prognostic parameter determining the risk of recurrence in PH. We suggest that AgNOR quantity may be a promising additional tool for predicting the biological behaviour of parathyroid lesions.

Quantitation of argyrophilic nucleolar organizer regions in regenerating muscle fibers in Duchenne and Becker muscular dystrophies and polymyositis

Abstract We have investigated the quantity of argyrophilic nucleolar organizer region (AgNOR) proteins in vastus lateralis muscle samples from 13 patients with Duchenne muscular dystrophy (DMD) (6 months–12 years), 9 with Becker muscular dystrophy (BMD) (13 months– 36 years), 9 with polymyositis (PM) (8–77 years) and 10 normal subjects (5 months–32 years). AgNORs were visualized on 4-μm-thick cryostat sections and quantified according to the guidelines of the Committee on AgNOR Quantitation; statistical analysis was performed on the mean AgNOR area (NORA) values. The mean NORA values encountered in DMD (4.327 ± 0.791 μm2), BMD (3.534 ± 0.312 μm2) and PM (3.785 ± 0.424 μm2) samples were significantly (P < 0.001) higher than those of normal muscle (1.682 ± 0.288 μm2); a value of P < 0.001 was also obtained when NORA values found in DMD were compared with those of BMD or PM. In addition, when NORA values were exclusively calculated in regenerating myofibers in DMD, BMD and PM, no differences were appreciable. On the other hand, in non-regenerating myofibers, the NORA values showed a significant increase in DMD versus BMD and PM (P < 0.001) as well as in each disease group versus controls. Our study documents that muscle diseases, such as DMD, BMD and PM in which regeneration is a constant finding, have a high rDNA transcriptional activity. In particular, our findings suggest that (1) regenerating nuclei behave in the same way in dystrophinopathies or PM; (2) virtually all nuclei, including quiescent-looking ones, are activated to realize an increased intracellular protein synthesis for proliferative and/ or functional purposes; and (3) the quantity of AgNOR does not seem related to age of patients at the time of biopsy.

PLEOMORPHIC CARCINOMA OF THE GALLBLADDER : REPORT OF A CASE

The authors report a rare case of primary pleomorphic carcinoma of the gallbladder in a 70-year-old woman. A polypoid tumor protruded into the lumen from the fundus of the gallbladder. Characteristic histologic findings Included a general lack of architectural cohesiveness, marked pleomorphism, presence of mononucleated and multinucleated giant cells, extensive necrosis, leukocyte-tumor cell phagocytosis or cannibalism. Immunoreactivity for cytokeratin, carclnoembryonic antigen and epithelial membrane antigen as well as histochemical positivity for mucins demonstrated the epithelial nature of the tumor. The neoplasm behaved aggressively; the patient died of metastases 9 months after the operation.