Should trichrome stain be used on all post-liver transplant biopsies with hepatitis C virus infection to estimate the fibrosis score?

Recurrent hepatitis C is virtually universal after liver transplantation; however, an individual patient's clinical course and disease burden are highly variable and difficult to predict. The fibrosis score determined on posttransplant biopsies appears to be a sensitive and specific marker of disease progression and severity. Currently, the fibrosis score is determined from hematoxylin and eosin (H&E)-stained tissue sections supplemented by variable use of trichrome stain or other connective tissue-specific stains. In this study, we compare the fibrosis score on H&E stain with that obtained with trichrome stain in posttransplant liver biopsies of patients with hepatitis C. A total of 197 liver biopsies from 105 allograft patients with hepatitis C were reviewed. The mean fibrosis stage was 1.0 +/- 1.25 with H&E stain versus 1.69 +/- 1.42 with trichrome stain (P < 0.00001). The trichrome staging score was higher in 53.3%, lower in 3%, and the same in 43.7%. The fibrosis stage was raised by 2 or more points in 17.8% and elevated into a bridging category in 14.7%. No significant differences in clinical and laboratory levels were measured in patients with higher fibrosis scores. In conclusion, the hepatic fibrosis score is significantly underestimated by H&E stain in the posttransplant setting in patients with hepatitis C. The fibrosis stage may be an indicator of significant liver damage in these patients. Accuracy of its determination may be most easily facilitated by employment of a connective tissue stain.

Coexpression of c-kit and bcl-2 in small cell carcinoma and large cell neuroendocrine carcinoma of the lung.

It has been shown that tyrosine kinase oncoprotein c-kit and antiapoptotic molecule bcl-2 are overexpressed in several types of malignancy, including small cell carcinoma (SCLC) and large cell neuroendocrine carcinoma (LCNEC) of the lung. Whether these 2 molecules are coexpressed in lung neuroendocrine tumors has not been investigated. Here, we analyzed immunohistochemical results to determine expression and coexpression patterns of c-kit and bcl-2 in the spectrum of lung neuroendocrine tumors. Using a polyclonal antibody against c-kit and a monoclonal antibody against bcl-2, our data demonstrated that all 7 cases (100%) of SCLC included in this study were positive for both c-kit and bcl-2. Among 14 LCNECs, 7 (50%) stained positive for c-kit and 9 (64%) for bcl-2. All cases of high grade neuroendocrine carcinomas (SCLCs and LCNECs) that showed positive staining for c-kit coexpressed bcl-2. In contrast, all typical and atypical carcinoids (TC and AC) were negative for c-kit, and only 1 of 16 (6.3%) TCs and 1 of 6 (16.7%) ACs stained positive for bcl-2. These results indicate a progressive increase in the frequency of c-kit and bcl-2 expression and coexpression, from carcinoid tumors (TC and AC) to LCNEC and to SCLC. High grade neuroendocrine carcinomas are more likely to coexpress c-kit and bcl-2 when compared with carcinoid tumors. The high frequency of coexpression of these 2 molecules in high grade neuroendocrine carcinomas of the lung suggests that they may be involved in the carcinogenic pathway, given their important roles in carcinogenesis. Therapeutic targeting on both c-kit and bcl-2 molecules might be beneficial in the management of patients with high grade neuroendocrine carcinomas of the lung in the future.

Enhanced synthesis of proinflammatory cytokines by vulvar vestibular fibroblasts: implications for vulvar vestibulitis.

OBJECTIVE: The objective of the study was to determine whether vestibular fibroblasts from vulvar vestibulitis (VVS) patients produce higher proinflammatory cytokine levels when provoked with Candida albicans (yeast) and alpha-melanocyte-stimulating hormone (alpha-MSH) in vitro. STUDY DESIGN: Twenty anatomically defined fibroblast strains from patients and age-matched controls were stimulated with 5 regimens: no stimulus, alpha-MSH, heat-killed yeast, alpha-MSH plus yeast, and interleukin (IL)-1beta. Supernatant products included the following: granulocyte macrophage colony-stimulating factor, interferon-gamma, IL-10, IL-12, IL-1beta, IL-2, IL-4, IL-6, IL-8, and tumor necrosis factor-alpha were assayed. RESULTS: Coincubation with alpha-MSH plus yeast significantly increased IL-6 (3-fold) and IL-8 (greater than 40-fold) production in patients and controls. Vestibular fibroblast exceeded external vulvar fibroblast production of IL-1beta, IL-6, and IL-8 following yeast alone and alpha-MSH plus yeast stimuli in patients and controls. Substratified by anatomic origin, vestibular fibroblasts from VVS patients produced the highest relative levels of IL-1beta, IL-6, and IL-8 at baseline and following the yeast-alone regimen. CONCLUSION: Localized pain of VVS may results from regionally elevated cytokines produced by vulvar vestibule-specific fibroblasts.

Human papillomavirus type 16 E7 up-regulates AKT activity through the retinoblastoma protein.

Human papillomaviruses (HPV) are small DNA tumor viruses causally associated with cervical cancer. The early gene product E7 from high-risk HPV is considered the major transforming protein expressed by the virus. Although many functions have been described for E7 in disrupting normal cellular processes, we describe in this study a new cellular target in primary human foreskin keratinocytes (HFK), the serine/threonine kinase AKT. Expression of HPV type 16 E7 in HFK caused inhibition of differentiation, hyperproliferation, and up-regulation of AKT activity in organotypic raft cultures. The ability of E7 to up-regulate AKT activity is dependent on its ability to bind to and inactivate the retinoblastoma (Rb) gene product family of proteins. Furthermore, we show that knocking down Rb alone, with short hairpin RNAs, was sufficient to up-regulate AKT activity in differentiated keratinocytes. Up-regulation of AKT activity and loss of Rb was also observed in HPV-positive cervical high-grade squamous intraepithelial lesions when compared with normal cervical tissue. Together, these data provide evidence linking inactivation of Rb by E7 in the up-regulation of AKT activity during cervical cancer progression.

Proteinase-activated receptor-2 stimulates prostaglandin production in keratinocytes: analysis of prostaglandin receptors on human melanocytes and effects of PGE2 and PGF2alpha on melanocyte dendricity.

Prostaglandins (PG) are key mediators of diverse functions in the skin and several reports suggest that PG mediate post-inflammatory pigmentary changes through modulation of melanocyte dendricity and melanin synthesis. The proteinase-activated receptor 2 (PAR-2) is important for skin pigmentation because activation of keratinocyte PAR-2 stimulates uptake of melanosomes through phagocytosis in a Rho-dependent manner. In this report, we show that activation of keratinocyte PAR-2 stimulates release of PGE(2) and PGF(2alpha) and that PGE(2) and PGF(2alpha) act as paracrine factors that stimulate melanocyte dendricity. We characterized the expression of the EP and FP receptors in human melanocytes and show that human melanocytes express EP1 and EP3, and the FP receptor, but not EP2 and EP4. Treatment of melanocytes with EP1 and EP3 receptor agonists resulted in increased melanocyte dendricity, indicating that both EP1 and EP3 receptor signaling contribute to PGE(2)-mediated melanocyte dendricity. Certain EP3 receptor subtypes have been shown to increase adenosine 3',5'-cyclic monophosphate (cAMP) through coupling to Gs, whereas EP1 is known to couple to Gq to activate phospholipase C with elevation in Ca(2+). The cAMP/protein kinase A system is known to modulate melanocyte dendrite formation through modulation of Rac and Rho activity. Neither PGF(2alpha) or PGE(2) elevated cAMP in human melanocytes showing that dendricity observed in response to PGE(2) and PGF(2alpha) is cAMP-independent. Our data suggest that PAR-2 mediates cutaneous pigmentation both through increased uptake of melanosomes by keratinocytes, as well as by release of PGE(2) and PGF(2alpha) that stimulate melanocyte dendricity through EP1, EP3, and FP receptors.