Probes for INS

Estrogen signalling pathways are emerging targets for lung cancer therapy. Unravelling the contribution of estrogens in lung cancer development is a pre-requisite to support the development of sex-based treatments and to identify patients who could potentially benefit from anti-estrogen treatments. In this study, we highlight the contribution of lymphatic and blood endothelia in the sex-dependent modulation of lung cancer. The orthotopic graft of syngeneic lung cancer cells into immunocompetent mice showed that lung tumours grew faster in female mice than in males. Moreover, estradiol (E2) promoted tumour development in female mice and increased lymph/angiogenesis and levels of VEGFA and bFGF in lung tumours of females through an estrogen receptor (ER) alpha-dependent pathway. Furthermore, while treatment with ERbeta antagonist was inefficient, ERalpha antagonist (MPP) and tamoxifen decreased lung tumour volumes, altered blood and lymphatic vasculature and reduced VEGFA and bFGF levels in females, but not in males. Finally, the quantification of lymphatic and blood vasculature of lung adenocarcinoma biopsies from patients aged between 35 to 55 years old revealed more extensive lymphangiogenesis and angiogenesis in tumour samples issued from women than from men. In conclusion, our findings highlight an E2/ERalpha-dependent modulation of lymphatic and blood vascular components of lung tumour microenvironment. Our study has potential clinical implication in a personalised medicine perspective by pointing to the importance of estrogen status or supplementation on lung cancer development that should be considered to adapt therapeutic strategies.

OBJECTIVES:

Albumin messenger RNA (mRNA) expression is a marker of hepatocellular differentiation. Most published data are from review of tissue microarrays, and albumin in situ hybridization (ISH) expression across several tumor types is incompletely characterized.

METHODS:

Sections from 221 tumors were evaluated for albumin mRNA. Immunohistochemistry was used to confirm diagnoses. Albumin ISH was performed according to manufacturer-provided instructions. Fifty-nine cases were evaluated with both commercial ISH assays.

RESULTS:

Albumin mRNA was detected in all hepatocellular carcinomas (HCCs) and 81% of intrahepatic cholangiocarcinomas. Lung (20%), gallbladder (39%), hepatoid pancreatic (n = 1 of 1) adenocarcinoma, breast invasive ductal carcinoma (18%), yolk sac tumor (25%), and acinar cell carcinoma (29%) showed expression. Both assays were concordant in 93% of cases.

CONCLUSIONS:

Albumin ISH was expressed in all HCCs studied. It was also positive in intrahepatic cholangiocarcinoma and patchy positive in gallbladder adenocarcinoma and a subset of other neoplasms, which can be a potential pitfall

Immunohistochemical (IHC) quantification of estrogen receptor-α (ER) is used for assessment of treatment regimen in breast cancer. Different ER IHC assays may produce diverging results, because of different antibody clones, protocols, and stainer platforms. Objective tissue-based techniques to assess sensitivity and specificity of IHC assays are therefore needed. We tested the usability of ER mRNA-in situ hybridization (mRNA-ISH) in comparison with assays based on clones SP1 and 6F11. We selected 56 archival specimens according to their reported ER IHC positivity, representing a wide spectrum from negative to strongly positive cases. The specimens were used to prepare 4 TMAs with 112 cores. Serial sections of each TMA were stained for ER and pan-cytokeratin (PCK) by IHC and ESR1 (ER gene) by mRNA-ISH. Digital image analysis (DIA) was used to determine ER IHC H-score. ESR1 mRNA-ISH was scored both manually and by DIA. DIA showed a nonlinear correlation between IHC and ESR1 mRNA-ISH with R-values of 0.80 and 0.78 for the ER antibody clones SP1 and 6F11, respectively. Comparison of manual mRNA-ISH scoring categories and SP1 and 6F11 IHC H-scores showed a highly significant relationship (P<0.001). In conclusion, the study showed good correlation between mRNA-ISH and IHC, suggesting that mRNA-ISH can be a valuable tool in the assessment of the sensitivity and specificity of ER IHC assays.

Abstract

OBJECTIVES:

Inconsistent data on detection of albumin expression by ribonucleic acid (RNA) in situ hybridization have been reported. We investigated the utility of RNAscope (Advanced Cell Diagnostics, Hayward, CA) in detection of albumin in hepatocellular carcinomas (HCCs), intrahepatic cholangiocarcinomas (ICCs), and carcinomas from various organs using manual and automated staining.

METHODS:

RNAscope for albumin detection was performed on 482 cases on tissue microarray sections and on 22 cases of ICC, including 14 surgical resection and eight core biopsy specimens.

RESULTS:

Thirty-six of 37 (97%) HCCs had detectable mRNA, whereas all non-HCC and non-ICC cases, except one lung adenocarcinoma, were negative for albumin. Fourteen of 22 ICCs (64%) were positive for albumin.

CONCLUSIONS:

RNAscope for albumin is highly sensitive and specific for identifying HCCs and is highly specific and moderately sensitive for detection of ICCs; however, rare carcinomas (non-HCC, non-ICC, and those with no hepatoid histomorphology) can also have aberrant expression of albumin.

Estrogen drives breast cancer (BCa) progression by directly activating estrogen receptor α (ERα). However, because of the stochastic nature of gene transcription, it is important to study the estrogen signaling pathway at the single-cell level to fully understand how ERα regulates transcription. Here, we performed single-cell transcriptome analysis on ERα-positive BCa cells following 17β-estradiol stimulation and reconstructed the dynamic estrogen-responsive transcriptional network from discrete time points into a pseudotemporal continuum. Notably, differentially expressed genes show an estrogen-stimulated metabolic switch that favors biosynthesis but reduces estrogen degradation. Moreover, folate-mediated one-carbon metabolism is reprogrammed through the mitochondrial folate pathway and polyamine and purine synthesis are upregulated coordinately. Finally, we show AZIN1 and PPAT are direct ERα targets that are essential for BCa cell survival and growth. In summary, our study highlights the dynamic transcriptional heterogeneity in ERα-positive BCa cells upon estrogen stimulation and uncovers a mechanism of estrogen-mediated metabolic switch.