Aberrant maspin expression in gallbladder epithelium is associated with intestinal metaplasia in patients with cholelithiasis

Practical Immunohistochemistry in Neoplastic Pathology of the Gastrointestinal Tract, Liver, Biliary Tract, and Pancreas

CONTEXT

- Immunomarkers with diagnostic, therapeutic, or prognostic values have been increasingly used to maximize the benefits of clinical management of patients with neoplastic diseases of the gastrointestinal tract, liver, biliary tract, and pancreas.

OBJECTIVES

- To review the characteristics of immunomarkers that are commonly used in surgical pathology practice for neoplasms of the gastrointestinal tract, liver, biliary tract, and pancreas, and to summarize the clinical usefulness of immunomarkers that have been discovered in recent years in these fields.

DATA SOURCES

- Data sources include literature review, authors' research data, and personal practice experience.

CONCLUSIONS

- Immunohistochemistry is an indispensable tool for the accurate diagnosis of neoplastic diseases of the gastrointestinal tract, liver, biliary tract, and pancreas. Useful immunomarkers are available to help distinguish malignant neoplasms from benign conditions, determine organ origins, and subclassify neoplasms that are morphologically and biologically heterogeneous. Specific immunomarkers are also available to help guide patient treatment and assess disease aggressiveness, which are keys to the success of personalized medicine. Pathologists will continue to play a critical role in the discovery, validation, and application of new biomarkers, which will ultimately improve patient care.

Epigenetic profiling of gallbladder cancer and gall stone diseases: Evaluation of role of tumour associated genes

BACKGROUND

As on today, the global mortality rate of gallbladder cancer is still very high. Both genetic and epigenetic alterations play pivotal roles in the development of cancer. We selected seven tumour associated genes, implicated in other cancers, to assess their methylation status in gallbladder cancer and gallstone diseases.

AIM OF STUDY

To study the promoter methylation of certain tumour associated genes in the molecular pathogenesis of gallbladder cancer and gall stone diseases.

MATERIALS AND METHODS

Methylation specific PCR for seven tumour associated genes, viz., MASPIN, 14-3-3 sigma gene, THBS1, FLNC, HLTF, COX-2 and SOCS1, was performed in 50 gallbladder cancer (GBC), 30 gall stone diseases (GSD) and their respective adjacent control tissues. Semi-quantitative PCR and immunohistochemistry was carried out to check the expression level. Student's t-test was carried out to compare the differences in the methylation and expression patterns between cases and control tissues.

RESULTS

We observed methylation of CpG islands in seven of the studied markers, but, the frequency of methylation was found varying among different samples. Of them, 14-33 sigma showed methylation in 45 GBC (90%; p=0.0001) and 25 GSD (86.66%; p=0.001), MASPIN in 35 GBC (70%; p=0.0008) and 18 GSD (51.43%; p=0.040), FLNC in 16 GBC (32%; p=0.0044) and 9 GSD (25.71%; p=ns), THBS1 in 26 GBC (52%; p=0.0009) and 10 GSD (28.57%; p=0.0505), HLTF in 8 GBC (16%; p=ns) and 2 GSD (5.71%; p=ns), COX2 in 10 GBC (20%; p=ns) and 6 GSD (17.14%; p=ns) and SOCS-1 in 3 GBC samples only (6%; p=ns), but not in GSD. Semi-quantitative PCR revealed down regulation in MASPIN, 14-3-3 sigma, THBS1, HLTF, COX2 and SOCS1 in advanced gallbladder cases. Immunohistochemistry further confirmed the down-regulation of SOCS1 in GBC.

CONCLUSION

The present study infers that accumulation of epigenetic alterations increases poor prognosis of GBC patients. Out of seven genes, MASPIN and THBS1 play key epigenetic role in GBC, but not in GSD. The reason for downregulation of SOCS1 only in GBC, and unaltered expression of 14-3-3 sigma protein in all the GBC and GSD tissue samples is not clear. Further investigation on the expression pattern of these genes in GBC cell lines may elucidate their likely functional role in in association with gallbladder cancer.

Diagnostic value of maspin in distinguishing adenocarcinoma from benign biliary epithelium on endoscopic bile duct biopsy

Histopathologic distinction between benign and malignant epithelia on endoscopic bile duct biopsy can be extremely challenging due to small sample size, crush artifact, and a propensity for marked inflammatory and reactive changes after stent placement. Our previous studies have shown that the insulin-like growth factor II mRNA-binding protein 3, S100P, and the von Hippel-Lindau gene product (pVHL) can help the distinction. This study analyzed 134 endoscopic bile duct biopsy specimens (adenocarcinoma 45, atypical 31, and benign 58) by immunohistochemistry for the expression of maspin, a serine protease inhibitor. The results demonstrated that (1) maspin expression was more frequently detected in malignant than in benign biopsies; (2) malignant biopsies frequently showed diffuse, strong/intermediate, and combined nuclear/cytoplasmic staining patterns for maspin, which were much less commonly seen in benign biopsies; (3) the malignant staining patterns for maspin observed in atypical biopsies were consistent with follow-up data showing that 67% of these patients were subsequently diagnosed with adenocarcinoma; (4) a maspin+/S100P+/pVHL- staining profile was seen in 75% of malignant biopsies but in none of the benign cases. These observations demonstrate that maspin is a useful addition to the diagnostic immunohistochemical panel (S100P, pVHL, and insulin-like growth factor II mRNA-binding protein 3) to help distinguish malignant from benign epithelia on challenging bile duct biopsies.

Incidental detection of carcinoma gall bladder in laparoscopic cholecystectomy specimens: a thirteen year study of 23 cases and literature review

Carcinoma of gall bladder is the most common malignancy of the biliary tract worldwide and is usually associated with poor prognosis. In this era of laparoscopic cholecystectomy, there has been increase in detection of early stage incidental gall bladder carcinoma in cholecystectomy specimens. A retrospective study was carried out in tertiary care hospital in central India. A total of 2990 patients underwent laparoscopic cholecystectomy during the year 2001-2013. Hospital records and histopathology reports of these patients were studied in detail. Twenty three cases of gall bladder carcinoma were detected incidentally accounting for an incidence of 0.76 %. It was more common in females with an M: F ratio of 1:1.9. Mean age of presentation was 57.8 years. Gall stones were present in 22 cases and one patient presented with features of acute cholecystitis. Three patients had associated xanthogranulomatous inflammation and 10 had associated intestinal metaplasia. It is not uncommon to encounter incidental malignancies of gall bladder in laparoscopic cholecystectomy specimens sent to histopathology for presumably benign disease. Histopathology reports must include comments on extent of infiltration, perineural invasion, tumor differentiation and nodal involvement for oncologist information and subsequent management of patients.

Utility of immunohistochemistry in the pancreatobiliary tract

CONTEXT

Immunohistochemistry has become a useful ancillary study in the identification and classification of pancreatic neoplasms. The diagnostic accuracy has been significantly improved because of the continuous discoveries of tumor-associated biomarkers and the development of effective immunohistochemical panels.

OBJECTIVES

To identify and classify pancreatic neoplasms by immunohistochemistry.

DATA SOURCES

Literature review and authors' research data and personal practice experience were used.

CONCLUSIONS

To better guide therapeutic decisions and predict the prognostic outcome, it is crucial to make an accurate diagnosis of a pancreatic neoplasm. Application of appropriate immunohistochemical panels enables pathologists to differentiate pancreaticobiliary adenocarcinomas from reactive conditions and to identify rare types of pancreatic neoplasms. Knowing the utilities and pitfalls of each tumor-associated biomarker is essential to avoiding a potential diagnostic error because an absolutely cancer-specific biomarker does not exist. This article reviews frequently used tumor-associated biomarkers, provides lists of effective immunohistochemical panels, and recommends a diagnostic algorithm as a standard approach to pancreatic neoplasms.

Elevated expression of maspin mRNA as a predictor of survival in stage II and III gallbladder cancer cases

BACKGROUND

Maspin expression is a potential prognostic factor for various malignancies but its relation with gallbladder cancer is unknown and needs to be investigated needs to be investigated. We therefore here focused on maspin mRNA expression in normal, gall stone disease and gallbladder cancer subjects, with particular attention to prognostic importance in individuals with malignancies.

MATERIALS AND METHODS

This study was carried out at the Department of Surgical Gastroenterology, King George's Medical University, Lucknow, India. Gallbladder samples from normal (n=25), gall stone disease (n=25) and cancer patients (n=38) were analysed for maspin mRNA expression by semi-quantitative reverse transcriptase PCR and quantitative real time PCR. Statistical analysis was carried out using the Students t test or ANOVA. Survival analysis was conducted according to the Kaplan-Meier method and correlations were assessed using the Pearson correlation method. p<0.05 was considered statistically significant.

RESULTS

Significant increase (p=0.028) in expression of maspin mRNA was observed in gallbladder cancer as compared to gall stone disease, whereas no expression was found in normal tissues. Significant correlation (Pearson's coefficient(r)=-0.798, p<0.0001) was observed between relative quantification of maspin mRNA and survival of cancer patients after surgery, with significantly shorter (p=0.002) survival in patients having relative quantification >1.5 as compared to those having relative quantification <1.5. Similarly, significant differences in patient survival for maspin mRNA expression was observed for stage II (p=0.025) and III (p=0.011) cancer.

CONCLUSIONS

Higher expression of maspin mRNA in gallbladder cancer has prognostic significance for stage II and III cancer, which needs to be investigated further.

Maspin: molecular mechanisms and therapeutic implications

Maspin, a non-inhibitory member of the serine protease inhibitor superfamily, has been characterized as a tumor suppressor gene in multiple cancer types. Among the established anti-tumor effects of Maspin are the inhibition of cancer cell invasion, attachment to extracellular matrices, increased sensitivity to apoptosis, and inhibition of angiogenesis. However, while significant experimental data support the role of Maspin as a tumor suppressor, clinical data regarding the prognostic implications of Maspin expression have led to conflicting results. This highlights the need for a better understanding of the context dependencies of Maspin in normal biology and how these are perturbed in the context of cancer. In this review, we outline the regulation and roles of Maspin in normal and developmental biology while discussing novel evidence and emerging theories related to its functions in cancer. We provide insight into the immense therapeutic potential of Maspin and the challenges related to its successful clinical translation.

Role of maspin in cancer

Maspin (mammary serine protease inhibitor), is a member of the serine protease inhibitor/non-inhibitor superfamily. Its expression is down-regulated in breast, prostate, gastric and melanoma cancers but over-expressed in pancreatic, gallbladder, colorectal, and thyroid cancers suggesting that maspin may play different activities in different cell types. However, maspin expression seems to be correlated with better prognosis in prostate, bladder, lung, gastric, colorectal, head and neck, thyroid and melanoma cancer. In breast and ovarian cancer maspin significance is associated with its subcellular localization: nucleus maspin expression correlates with a good prognosis, whilst in pancreatic cancer it predicts a poor prognosis. Since tumor metastasis requires the detachment and invasion of tumor cells through the basement membrane and stroma, a selectively increased adhesion by the presence of maspin may contribute to the inhibition of tumor metastasis. Furthermore the different position of maspin inside the cell or its epigenetic modifications may explain the different behavior of the expression of maspin between tumors. The expression of maspin might be useful as a prognostic and possibly predictive factor for patients with particular types of cancer and data can guide physicians in selecting therapy. Its expression in circulating tumor cells especially in breast cancer, could be also useful in clinical practice along with other factors, such as age, comorbidities, blood examinations in order to select the best therapy to be carried out. Focusing on the malignancies in which maspin showed a positive prognostic value, therapeutic approaches studied so far aimed to re-activate a dormant tumor suppressor gene by designed transcription factors, to hit the system that inhibits the expression of maspin, to identify natural substances that can determine the activation and the expression of maspin or possible “molecules binds” to introduce maspin in cancer cell and gene therapy capable of up-regulating the maspin in an attempt to reduce primarily the risk of metastasis.

Further studies in these directions are necessary to better define the therapeutic implication of maspin.

Expression of the homeostasis-related markers, maspin, heat shock proteins 70 & 90, glutathione S-transferase, aquaporin 5 and NF-kB in young and old labial and palatal salivary glands

Intraoral salivary glands undergo remarkable age-related morphologic changes. This study investigated the expression of a panel of molecular markers known for cellular homeostatic activity, dependent on age and location of the salivary glands. Samples taken from healthy subjects were classified according to age ("young" <45 years, n=51, and "old" ≥60 years, n=45) and location (lip, n=47 and palate, n=49). They were immunohistochemically stained for mammary serine protease inhibitor (maspin), heat shock protein (HSP)70, HSP90, glutathione S-transferase (GST), aquaporine5 (AQP5), and nuclear factor kappa-B (NF-κB) for assessment of their expression in acini and ducts, and in cytoplasmic and nuclear compartments. Results were expressed as the mean percentage of positively stained component per age group, gland location and type of cell and cellular compartment. Statistical analysis was performed by two-way ANOVA and crosstabs. The expression of maspin was lower in the old group in both the palatal and labial glands (acini and ducts, cytoplasm and nuclei) compared to the young group (p<0.05). In both age groups, when compared to labial glands, palatal glands exhibited higher expression of HSP70 (p<0.05) and lower expression of AQP5 (p<0.001) and NF-κB (p=0.018). Collectively, the low expression of factors capable of preserving cellular homeostasis (i.e., maspin and AQP5) vis-à-vis a high expression of factors that are also related to cell survival (i.e., HSPs) that was demonstrated in the old palatal glands may point to their high vulnerability to undergo selective phenotypic changes.

Diagnostic utility of von Hippel-Lindau gene product, maspin, IMP3, and S100P in adenocarcinoma of the gallbladder

Our recent study demonstrated the up-regulation of maspin, IMP3, and S100P and down-regulation of von Hippel-Lindau gene product (pVHL) in ductal adenocarcinoma of the pancreas. Distinction of adenocarcinoma of the gallbladder from benign/reactive glandular epithelium can be challenging if based on hematoxylin and eosin-stained sections alone. Immunohistochemical stains for pVHL, maspin, IMP3, and S100P were performed on 82 gallbladder specimens, including adenocarcinoma (n = 33) and normal/reactive gallbladder (n = 49). The results demonstrated (1) only 6.0% of adenocarcinoma cases were focally positive for pVHL, and all normal and most reactive cases (85%) were diffusely positive for pVHL; (2) maspin, IMP3, and S100P were positive in 100%, 81.8%, and 75.8% of adenocarcinoma cases, respectively; in contrast, 53.1%, 12.2%, and 30.6% of normal/reactive cases were only focally and weakly positive for maspin, IMP3, and S100P, respectively; and (3) 90.3% of adenocarcinoma cases were pVHL-negative and positive for 2 or more positive markers, whereas none of the benign/reactive cases showed this staining profile. This study demonstrates that the immunostaining profile of pVHL-/IMP3+/maspin+/S100P+ is useful in the distinction of adenocarcinoma of the gallbladder from normal/reactive conditions.

Intestinal metaplasia in gallbladder correlates with high amylase levels in bile in patients with a morphologically normal pancreaticobiliary duct

We reported previously that intestinal metaplasia in the gallbladder is strongly associated with expression of caudal-related homeobox transcription factor Cdx2. It has been documented that occult pancreatobiliary reflux, even in the absence of pancreaticobiliary maljunction, is associated with elevated risk of biliary malignancy. We ascertained the correlation between intestinal metaplasia in the gallbladder and occult pancreatobiliary reflux. In 196 patients with a normal pancreaticobiliary ductal arrangement who had undergone laparoscopic cholecystectomy, we performed intraoperative cholangiography and measured amylase levels in bile sampled from the gallbladder. The cutoff value for high cystic amylase was defined as a biliary amylase level higher than the normal upper limit of serum amylase (215 IU/L). We also retrospectively reviewed the cholecystectomized tissue specimens to investigate the presence of intestinal metaplasia and expression of Cdx2. Then, we explored the relationship between intestinal metaplasia in the gallbladder and occult choledocho-pancreatic reflux. Intestinal metaplasia was found in 16.8% (33/196) of the gallbladders. The prevalence of choledocho-pancreatic reflux revealed by intraoperative cholangiography was not significantly different between cases with intestinal metaplasia (5/33, 15.2%) and those without (25/163, 15.3%; P = .81). However, in cases with intestinal metaplasia, the rate of high cystic amylase (13/33, 39.4%) was significantly higher compared with cases without intestinal metaplasia (26/163, 16.0%, P = .005). In conclusion, intestinal metaplasia in the gallbladder is significantly correlated with high amylase levels in bile in patients with a morphologically normal pancreaticobiliary ductal arrangement.

Maspin Expression in Oral Squamous Cell Carcinoma

Maspin (mammary serine protease inhibitor) is a member of the serpin superfamily of protease inhibitors and it has a role as a tumor suppressor. Maspin has been reported to be important in processes relevant to tumor growth and metastasis such as cell invasion, angiogenesis, and apoptosis. A high expression of maspin was correlated with better rates of survival and absence of nodal metastases in head and neck squamous cell carcinoma. In contrast, some studies have shown that maspin overexpression is correlated with a poor prognosis in pancreatic and ovarian cancers and in lung adenocarcinoma. The aim of this study was an immunohistochemical evaluation of the maspin expression in oral squamous cell carcinoma and thus 89 patients were evaluated. Maspin expression in oral squamous cell carcinoma was significantly associated with the tumor differentiation grade (chi test: P = 0.0318) and the lymph node status (chi test: P < 0.005), but not with the tumor stage (chi test: P = 0.666). Metastatic involvement of lymph nodes was observed more frequently in maspin-negative cases than in tumors with more than 5% of positive cells (P = 0.0024). The present results confirm that maspin expression predicts a better prognosis in oral squamous cell carcinoma and that maspin probably plays a role in tumor progression.

A close relationship between intestinal metaplasia and Cdx2 expression in human gallbladders with cholelithiasis

We previously reported a case of a human gallbladder with cholelithiasis consisting of intestinal metaplasia with the expression of caudal-related homeobox transcription factor (Cdx2). However, it is unclear how often intestinal metaplasia and Cdx2 expression occur in human, nontumorous gallbladders with cholelithiasis. We studied the incidence of intestinal metaplasia and Cdx2 expression in human gallbladders with cholelithiasis. Gallbladders were resected under laparoscopy from 103 patients with cholelithiasis between September 2003 and March 2005. The mean age of the patients was 59.6 +/- 15.0 years (range, 22-92 years). We retrospectively reviewed these cases to look for the presence of intestinal metaplasia and the expression of Cdx2. In addition, the characteristics of intestinal metaplasia were examined by immunostaining for Muc2, chromogranin A, and serotonin. Intestinal metaplasia was found in 11.7% (12/103) of the gallbladders with cholelithiasis. The mean ages of patients with and without intestinal metaplasia were 60.8 +/- 15.4 and 59.4 +/- 14.9 years, respectively. Cdx2, Muc2, chromogranin A, and serotonin were expressed in 91.7% (11/12), 91.7% (11/12), 83.3% (10/12), and 50.0% (6/12) in intestinal metaplastic mucosa, respectively. Only one case (1.1%) that expressed Cdx2 without intestinal metaplasia did not express Muc2, chromogranin A, and serotonin. We found that 10.7% (11/103) of nontumorous gallbladders resected because of cholelithiasis under laparoscopy revealed intestinal metaplasia with Cdx2 expression.

Maspin: the new frontier

Maspin (mammary serine protease inhibitor) was identified in 1994 by subtractive hybridization analysis of normal mammary tissue and breast cancer cell lines. Subsequently, emerging evidence portrays maspin as a multifaceted protein, interacting with diverse group of intercellular and extracellular proteins, regulating cell adhesion, motility, apoptosis, and angiogenesis and critically involved in mammary gland development. The tissue-specific expression of maspin is epigenetically controlled, and aberrant methylation of maspin promoter is closely associated with maspin gene silencing. Identification of new tissue sites expressing maspin and novel maspin-binding partners has expanded the horizon for maspin research and promises maspin-based therapeutic approaches for combating cancer. This perspective briefly outlines the past and present strides in deciphering this unique molecule and speculates on new frontiers in maspin research and prospects of maspin as a diagnostic/prognostic indicator in cancer.