BRAFV600E, hypothyroidism, and human relaxin in thyroid carcinogenesis.

PURPOSE: BRAFV600E, a major driver of thyroid cancer, evaluated in the context of thyroid hormones and human relaxin. METHODS: Immunohistochemical expressions of BRAFV600E, TSH, TSH receptor (TSHR), T4, T3 receptor (T3R), RLNH2, and its receptor, RXFP1, were evaluated in thyroid tumors from a retrospective U.S. population of 481 cancer cases diagnosed in 1983-2004. RESULTS: BRAFV600E was expressed in 52% of all thyroid tumors; expression of other markers ranged from 25% for T4 to 98% for RLNH2. Tumors predominantly exhibited hypothyroid-like conditions characterized by elevated TSH and TSHR and reduced T4. BRAFV600E prevalence was significantly higher in tumors expressing TSH, TSHR, T3R, and RXFP1 and lower in tumors expressing T4. The proportion of BRAFV600E mutation in classic papillary tumors significantly increased from 56 to 72% over the 21-year period of diagnoses, while expression of RXFP1, TSH, TSHR, and T3R decreased in non-tumor. Racial/ethnic differences were observed in thyroid hormone marker expression. Non-tumor expression of TSH, TSHR, and T3R were each associated with shorter overall survival, but did not remain significant after adjustment for demographic and clinical factors. CONCLUSIONS: Our study provides the first evidence of the potential interaction of BRAFV600E mutation, relaxin, and thyroid hormones in thyroid carcinogenesis. Moreover, our results suggest that hypothyroidism, influenced by RLNH2 activity, may underlie the development of the majority of thyroid cancers and mediate the role of BRAFV600E in thyroid carcinogenesis. BRAFV600E mutation is increasing in papillary thyroid cancers and may be contributing to the rising incidence of this malignancy.

Breast tumor tissue inflammation but not lobular involution is associated with survival among breast cancer patients in the Multiethnic Cohort.

BACKGROUND: This study investigated the association of breast lobular involution status and three inflammatory markers as predictors of survival among breast cancer patients in the Multiethnic Cohort. METHODS: Lobular involution was evaluated in tissue sections of normal breast tissue and COX-2, TNF-α, and TGF-ß proteins were assessed by immunohistochemistry in tumor microarrays. A summary score added the expression levels of the three markers. Cox regression was applied to estimate hazard ratios (HRs) and 95 % confidence intervals (CI) with age as the time metric and adjustment for factors known to affect mortality. RESULTS: Among 254 women (mean age = 61.7 ± 8.7 years) with pathologic blocks and follow-up information, 54 all-cause and 10 breast cancer-specific deaths were identified after a mean follow-up time of 16.0 ± 3.1 years. For 214 participants, an inflammatory score was available and 157 women had information on lobular involution. Lobular involution was not significantly associated with survival. Expression of both COX-2 and TNF-α were significant predictors of lower survival (p = 0.02 and 0.04), while the association for TGF-ß was weaker (p = 0.09). When combined into one overall inflammation score, both intermediate (HR = 2.72; 95 % CI 0.90-8.28) and high (HR = 4.21; 95 % CI 1.51-11.8) scores were associated with higher mortality but only the latter was statistically significant. No significant association with breast cancer-specific mortality was detected. CONCLUSIONS: These results suggest that strong expression of inflammatory markers in breast tissue predicts a poorer prognosis possibly due to a system-wide state of chronic inflammation.

Mammographic density and breast tissue expression of inflammatory markers, growth factors, and vimentin.

BACKGROUND: Mammographic density is a known risk factor for breast cancer, but the underlying pathologic characteristics are not well understood. The current analysis investigated the expression of several markers of interest, e.g., inflammation and growth, with mammographic density (MD) in normal and malignant breast tissue specimens from 279 women of the Multiethnic Cohort (MEC). METHODS: Breast cancer cases, recruited from a nested case-control study within the MEC, provided mammograms for density evaluation. Protein expression (COX-2, TNF-α, TGF-ß, IGF-1R, IGFBP-2, and vimentin) was assessed by immunohistochemical detection. Linear regression was applied to evaluate the relation between marker expression and percent density and to compute adjusted means with 95% confidence intervals (CI) by marker status while adjusting for confounders. RESULTS: Due to missing cores and tissue, normal tissue could only be evaluated for COX-2 and vimentin. No significant associations with mammographic density were detected for all markers analyzed. For inflammatory markers (TNF-α, COX-2, and TGF-ß) in tumor tissue, MD were non-significantly higher with stronger expression but the differences were very small. For example, the mean MD values for no, weak, and strong TNF-α expression were 35% (95% CI 24-47%), 39% (95% CI 29-48%), and 38% (95% CI 27-50%). In a posthoc analysis among postmenopausal women only, the difference across categories of TNF-α expression increased to 25% (95% CI 12-39%), 35% (95% CI 23-48%), and 35% (95% CI 20-49%). CONCLUSIONS: The current analysis offers little support for an involvement of immunohistochemical markers representing inflammatory and growth factor pathways as predictors of breast density.

Calpain-2 inhibitor treatment preferentially reduces tumor progression for human colon cancer cells expressing highest levels of this enzyme.

Calpain-2 levels are higher in colorectal tumors resistant to chemotherapy and previous work showed calpain-2 inhibitor therapy reduced inflammation-driven colorectal cancer, but direct effects of the inhibitor on colon cancer cells themselves were not demonstrated. In the present study, five human colon cancer cell lines were directly treated with a calpain-2 inhibitor and results showed increased cell death in 4 of 5 cell lines and decreased anchorage-independent growth for all cell five lines. When tested for levels of calpain-2, three cell lines exhibited increasing levels of this enzyme: HCT15 (low), HCC2998 (medium), and HCT116 (significantly higher). This was consistent with gel shift assays showing that calpain-2 inhibitor reduced of NF-κB nuclear translocation most effectively in HCT116 cells. Ability of calpain-2 inhibitor to impede tumor progression in vivo was evaluated using intrarectal transplant of luciferase-expressing cells for these three cell lines. Results showed that calpain-2 inhibitor therapy reduced tumor growth and increased survival only in mice injected with HCT116 cells. These data suggest calpain-2 inhibitor treatment may be most effective on colorectal tumors expressing highest levels of calpain-2.

Involution of breast tissue and mammographic density.

BACKGROUND: Mammographic density decreases and involution of breast tissue increases with age; both are thought to be risk factors for breast cancer. The current study investigated the relationship between involution or hormone treatment (HT) and breast density among multiethnic patients with breast cancer in Hawaii. METHODS: Patients with breast cancer cases were recruited from a nested case-control study within the Multiethnic Cohort. HT use was self-reported at cohort entry and at the time of the density study. Mammographic density and involution in adjacent non-tumor breast tissue were assessed using established methods. Linear regression was applied to evaluate the correlation between involution and four density measures and to compute adjusted means by involution status while adjusting for confounders. RESULTS: In the 173 patients with breast cancer, mean percent breast density was 41.2% in mammograms taken approximately 1 year before diagnosis. The respective proportions of women with no, partial, and complete involution were 18.5, 51.4, and 30.1%, respectively and the adjusted density values for these categories were 32.5, 39.2, and 40.2% (p = 0.15). In contrast, the size of the dense area was significantly associated with involution (p = 0.001); the values ranged from 29.7 cm2 for no involution to 48.0 cm2 for complete involution. The size of the total breast area but not of the non-dense areas was also larger with progressive involution. Percent density and dense area were significantly higher in women with combined HT use. CONCLUSIONS: Contrary to previous reports, greater lobular involution was not related to lower mammographic density but to higher dense area. Possibly, percent density during the involution process depends on the timing of mammographic density assessment, as epithelial tissue is first replaced with radiographically dense stromal tissue and only later with fat.

Differences in IGF-axis protein expression and survival among multiethnic breast cancer patients.

There is limited knowledge about the biological basis of racial/ethnic disparities in breast cancer outcomes. Aberrations in IGF signaling induced by obesity and other factors may contribute to these disparities. This study examines the expression profiles of the insulin-like growth factor (IGF)-axis proteins and the association with breast cancer survival across a multiethnic population. We examined the expression profiles of the IGF1, IGF1R, IGFBP2 (IGF-binding proteins), and IGFBP3 proteins in breast tumor tissue and their relationships with all-cause and breast cancer-specific survival up to 17 years postdiagnosis in a multiethnic series of 358 patients in Hawaii, USA. Native Hawaiians, Caucasians, and Japanese were compared. Covariates included demographic and clinical factors and ER/PR/HER2 (estrogen receptor/progesterone receptor/human epidermal growth factor receptor-2) status. In Native Hawaiian patients, IGFBP2 and IGFBP3 expression were each independently associated with overall and breast cancer mortality (IGFB2: HR(mort) = 10.96, 95% CI: 2.18-55.19 and HR(mort) = 35.75, 95% CI: 3.64-350.95, respectively; IGFBP3: HR(mort) = 5.16, 95% CI: 1.27-20.94 and HR(mort) = 8.60, 95% CI: 1.84-40.15, respectively). IGF1R expression was also positively associated with all-cause mortality in Native Hawaiians. No association of IGF-axis protein expression and survival was observed in Japanese or Caucasian patients. The interaction of race/ethnicity and IGFBP3 expression on mortality risk was significant. IGF-axis proteins may have variable influence on breast cancer progression across different racial/ethnic groups. Expression of binding proteins and receptors in breast tumors may influence survival in breast cancer patients by inducing aberrations in IGF signaling and/or through IGF-independent mechanisms. Additional studies to evaluate the role of the IGF-axis in breast cancer are critical to improve targeted breast cancer treatment strategies.

Viral hepatitis markers in liver tissue in relation to serostatus in hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) incidence is increasing in the United States. Hepatitis B virus (HBV) and hepatitis C virus (HCV) are major causes of HCC. Hepatitis infection in patients with HCC is generally diagnosed by serology, which is not always consistent with the presence of HBV and HCV in the liver. The relationship of liver viral status to serostatus in hepatocarcinogenesis is not fully understood. METHODS: HBV and HCV were evaluated in formalin-fixed, paraffin-embedded liver tissue specimens in a retrospective study of 61 U.S. HCC cases of known serologic status. HBV DNA and HCV RNA were detected by PCR, reverse transcription PCR (RT-PCR), and pyrosequencing, and HBsAg and HBcAg were evaluated by immunohistochemistry. RESULTS: Viral markers were detected in the liver tissue of 25 of 61 (41%) HCC cases. Tissue viral and serologic status were discordant in 27 (44%) cases, including those with apparent "occult" infection. Specifically, HBV DNA was detected in tissue of 4 of 39 (10%) serum HBsAg (-) cases, including 1 anti-HCV(+) case; and HCV RNA was detected in tissue of 3 of 42 (7%) anti-HCV seronegative cases, including two with serologic evidence of HBV. CONCLUSIONS: Viral hepatitis, including HBV-HCV coinfection, may be unrecognized in up to 17% of patients with HCC when based on serology alone. Further research is needed to understand the clinical significance of viral makers in liver tissue of patients with HCC in the absence of serologic indices. IMPACT: The contribution of HBV and HCV to the increasing incidence of HCC in the United States may be underestimated.

Agreement for tumor grade of ovarian carcinoma: analysis of archival tissues from the surveillance, epidemiology, and end results residual tissue repository.

BACKGROUND: Emerging data suggest that ovarian cancers differ by tumor grade. However, the reliability of microscopic grade from paraffin tissue in the general medical community and as reflected in population-based cancer registries is unknown. METHODS: We examined grade agreement between two gynecologic pathologists and the Surveillance Epidemiology and End Results Residual Tissue Repository (SEER). Grade agreement was assessed with percent observer agreement and kappa coefficients for 664 invasive ovarian carcinomas, using previously defined three-tier and two-tier grading systems. A random subset of ovarian carcinomas was selected to compare intra- and inter-pathologist agreement. RESULTS: Five hundred and eighty-six of SEER's 664 tumors were confirmed invasive. Percent agreement was 49 % with fair kappa coefficient = 0.25 (95 % CI: 0.20-0.30) for the 664 tumors. Agreement improved slightly when restricted to the 586 confirmed invasive cancers; it was better for high grade than low grade tumors, for two-tier than three-tier grading systems, and within (66 %) than between study pathologists (43 %). Grade was not a robust independent predictor of ovarian cancer-specific survival. CONCLUSIONS: Grade agreement was fair between SEER and study pathologists irrespective of grading system. Recorded grade in SEER should be used with caution and is probably not a reliable metric for ovarian cancer epidemiology.

BRCA1-IRIS overexpression promotes formation of aggressive breast cancers.

INTRODUCTION: Women with HER2(+) or triple negative/basal-like (TN/BL) breast cancers succumb to their cancer rapidly due, in part to acquired Herceptin resistance and lack of TN/BL-targeted therapies. BRCA1-IRIS is a recently discovered, 1399 residue, BRCA1 locus alternative product, which while sharing 1365 residues with the full-length product of this tumor suppressor gene, BRCA1/p220, it has oncoprotein-like properties. Here, we examine whether BRCA1-IRIS is a valuable treatment target for HER2(+) and/or TN/BL tumors. METHODOLOGY/PRINCIPAL FINDINGS: Immunohistochemical staining of large cohort of human breast tumor samples using new monoclonal anti-BRCA1-IRIS antibody, followed by correlation of BRCA1-IRIS expression with that of AKT1, AKT2, p-AKT, survivin and BRCA1/p220, tumor status and age at diagnosis. Generation of subcutaneous tumors in SCID mice using human mammary epithelial (HME) cells overexpressing TERT/LT/BRCA1-IRIS, followed by comparing AKT, survivin, and BRCA1/p220 expression, tumor status and aggressiveness in these tumors to that in tumors developed using TERT/LT/Ras(V12)-overexpressing HME cells. Induction of primary and invasive rat mammary tumors using the carcinogen N-methyl-N-nitrosourea (NMU), followed by analysis of rat BRCA1-IRIS and ERα mRNA levels in these tumors. High BRCA1-IRIS expression was detected in the majority of human breast tumors analyzed, which was positively correlated with that of AKT1-, AKT2-, p-AKT-, survivin, but negatively with BRCA1/p220 expression. BRCA1-IRIS-positivity induced high-grade, early onset and metastatic HER2(+) or TN/BL tumors. TERT/LT/BRCA1-IRIS overexpressing HME cells formed invasive subcutaneous tumors that express high AKT1, AKT2, p-AKT and vimentin, but no CK19, p63 or BRCA1/p220. NMU-induced primary and invasive rat breast cancers expressed high levels of rat BRCA1-IRIS mRNA but low levels of rat ERα mRNA. CONCLUSION/SIGNIFICANCE: BRCA1-IRIS overexpression triggers aggressive breast tumor formation, especially in patients with HER2(+) or TN/BL subtypes. We propose that BRCA1-IRIS inhibition may be pursued as a novel therapeutic option to treat these aggressive breast tumor subtypes.

Geminin overexpression induces mammary tumors via suppressing cytokinesis.

Aneuploidy plays an important role in the development of cancer. Here, we uncovered an oncogenic role for geminin in mitotic cells. In addition to chromatin, tyrosine phosphorylated geminin also localizes to centrosome, spindle, cleavage furrow and midbody during mitosis. Geminin binding to Aurora B prevents its binding to INCENP, and thus activation leading to lack of histone H3-(serine 10) phosphorylation, chromosome condensation failure, aborted cytokinesis and the formation of aneuploid, drug resistance cells. Geminin overexpressing human mammary epithelial cells form aneuploid, aggressive tumors in SCID mice. Geminin is overexpressed in more than half of all breast cancers analyzed. The current study reveals that geminin is a genuine oncogene that promotes cytokinesis failure and production of aneuploid, aggressive breast tumors when overexpressed and thus a worthy therapeutic target (oncotarget) for aggressive breast cancer.