Hepatocyte Nuclear Factor-1β Expression in Clear Cell Renal Cell Carcinoma and Urothelial Carcinoma With Clear Cell Features: A Potential Diagnostic Pitfall

HNF-1β is a More Sensitive and Specific Marker Than C-Reactive Protein for Identifying Biliary Differentiation in Primary Hepatic Carcinomas

CONTEXT.—

Intrahepatic cholangiocarcinoma (iCCA) needs to be distinguished from hepatocellular carcinoma (HCC) and metastasis, and in the absence of any specific biliary markers, is often a diagnosis of exclusion. Hepatocyte nuclear factor (HNF)-1β is a transcription factor that plays a critical role in bile duct system morphogenesis.

OBJECTIVE.—

To investigate the diagnostic value of HNF-1β to differentiate iCCA from HCC by immunohistochemistry and compare HNF-1β with C-reactive protein (CRP), a previously identified marker for iCCA.

DESIGN.—

Cases of iCCA (n = 75), combined hepatocellular-cholangiocarcinoma (cHCC-CCA) (n = 13) and HCC (n = 65) were included in the study.

RESULTS.—

All cases of iCCA (74 of 74, 100%) expressed HNF-1β compared with CRP expressed in 72.60% (53 of 73). The sensitivity and specificity of HNF-1β to differentiate iCCA from HCC was 100% and 92.31%, whereas the sensitivity and specificity for CRP was 75.58% and 7.79%. The expression of HNF-1β was greater in iCCA and the CCA component of cHCC-CCA compared with CRP (87 of 87, 100% versus 65 of 86, 75.58%, P < .001). On the contrary, CRP was more frequently expressed compared with HNF-1β in HCC and HCC component of cHCC-CCA (71 of 77, 92.21% versus 6 of 78, 7.69%; P < .001).

CONCLUSIONS.—

Our data indicate that HNF-1β is a more sensitive and specific marker than CRP for the diagnosis of iCCA and to identify the CCA component in cHCC-CCA. Lack of HNF-1β expression may be used to exclude iCCA from consideration in cases of adenocarcinomas of unknown primary.

Transcription factors in epithelial ovarian cancer: histotype-specific drivers and novel therapeutic targets

Transcription factors (TFs) are major contributors to cancer risk and somatic development. In preclinical and clinical studies, direct or indirect inhibition of TF-mediated oncogenic gene expression profiles have proven to be effective in many tumor types, highlighting this group of proteins as valuable therapeutic targets. In spite of this, our understanding of TFs in epithelial ovarian cancer (EOC) is relatively limited. EOC is a heterogeneous disease composed of five major histologic subtypes; high-grade serous, low-grade serous, endometrioid, clear cell and mucinous. Each histology is associated with unique clinical etiologies, sensitivity to therapies, and molecular signatures - including diverse transcriptional regulatory programs. While some TFs are shared across EOC subtypes, a set of TFs are expressed in a histotype-specific manner and likely explain part of the histologic diversity of EOC subtypes. Targeting TFs present with unique opportunities for development of novel precision medicine strategies for ovarian cancer. This article reviews the critical TFs in EOC subtypes and highlights the potential of exploiting TFs as biomarkers and therapeutic targets.

Genomic and Molecular Abnormalities in Gynecologic Clear Cell Carcinoma

Gynecologic clear cell carcinoma is a rare histology, accounting for ~5% of all ovarian and endometrial cancers in the United States. Compared to other types of gynecologic cancer, they are generally less responsive to standard therapy and have an overall worse prognosis. In addition, mounting evidence suggests that the landscape of genetic and molecular abnormalities observed in these tumors is distinct from other cancers that arise from the same sites of origin. On a molecular level, these tumors characteristically display upregulation of the PI3K-AKT-mTOR and RAS-RAF-MAPK signaling axes, frequent loss of ARID1a, and overexpression of MDM2. Evidence also suggests that these tumors are more likely to express programmed death ligand 1 or demonstrate microsatellite instability than other gynecologic cancers. Despite these important differences, there has been relatively little investigation into histology-specific treatment of clear cell gynecologic cancers, representing an opportunity for new drug development. In this article, we review the unique genetic and molecular features of gynecologic clear cell cancers with an emphasis on potential therapeutic targets. The results of completed studies of treatment for clear cell carcinoma are also presented. We conclude with a discussion of ongoing clinical trials and potential avenues for future study.