Noninvasive measurement of the distribution and oxygenation state of hemoglobin (Hb) inside the tissue is strongly required to analyze the tumor-associated vasculatures. We developed a photoacoustic imaging (PAI) system with a hemispherical-shaped detector array (HDA). Here, we show that PAI system with HDA revealed finer vasculature, more detailed blood-vessel branching structures, and more detailed morphological vessel characteristics compared with MRI by the use of breast shape deformation of MRI to PAI and their fused image. Morphologically abnormal peritumoral blood vessel features, including centripetal photoacoustic signals and disruption or narrowing of vessel signals, were observed and intratumoral signals were detected by PAI in breast cancer tissues as a result of the clinical study of 22 malignant cases. Interestingly, it was also possible to analyze anticancer treatment-driven changes in vascular morphological features and function, such as improvement of intratumoral blood perfusion and relevant changes in intravascular hemoglobin saturation of oxygen. This clinical study indicated that PAI appears to be a promising tool for noninvasive analysis of human blood vessels and may contribute to improve cancer diagnosis.

Background Blocking the PD-1 pathway induces immune-related adverse events (irAEs) which often involve the thyroid gland (thyroid irAEs). Clinical features of a thyroid irAE including its predictability and relationship to prognosis remain to be elucidated. Methods Two hundred consecutive patients treated with nivolumab at Kyoto University Hospital between September 1, 2014 and August 31, 2017 were included in a retrospective cohort study. We systematically determined and classified subclinical and overt thyroid irAEs based on data collected of serum free T4 and TSH levels. Baseline characteristics and detailed clinical data were analyzed, and analyses of overall survival (OS) excluded patients censored within 1 month from the first administration of nivolumab. Results Sixty-seven patients (33.5%) developed thyroid irAEs and these were divided into a subclinical thyroid irAE group ( n = 40, 20.0%) and an overt thyroid irAE group ( n = 27, 13.5%). Patients with thyroid uptake of FDG-PET before treatment showed high incidences of overt thyroid irAE (adjusted odds ratio 14.48; 95% confidence interval [CI] 3.12–67.19), while the same relationship was not seen with subclinical thyroid irAE. Regarding the total cohort, the thyroid irAE (+) group had a significantly longer median OS than the thyroid irAE (−) group (16.1 versus 13.6 months, hazard ratio [HR] 0.61; 95% CI 0.39–0.93). In 112 non-excluded patients with lung cancer, the thyroid irAE (+) group similarly had a longer median OS than the thyroid irAE (−) group (not reached versus 14.2 months, HR 0.51; 95% CI 0.27–0.92). However, this observation was not seen in 41 non-excluded patients with malignant melanoma (12.0 versus 18.3 months, HR 1.54; 95% CI 0.67–3.43). Conclusions By thyroid uptake of FDG-PET, overt thyroid irAEs could be predicted before nivolumab therapy. Thyroid irAEs related to good prognosis in lung cancer but might be inconclusive in malignant melanoma.

High-resolution matrix-assisted laser desorption ⁄ ionization imaging mass spectrometry (MALDI IMS) is an emerging application for lipid research that provides a comprehensive and detailed spatial distribution of ionized molecules. Recent lipidomic approach has identified several phospholipids and phosphatidylinositols (PIs) are accumulated in breast cancer tissues and are therefore novel biomarker candidates. Because their distribution and significance remain unclear, we investigated the precise spatial distribution of PIs in human breast cancer tissues using highresolution MALDI IMS. We evaluated tissues from nine human breast cancers and one normal mammary gland by negative ion MALDI IMS at a resolution of 10 lm. We detected 10 PIs with different fatty acid compositions, and their proportions were remarkably variable in the malignant epithelial regions. Highresolution imaging enabled us to discriminate cancer cell clusters from the adjacent stromal tissue within epithelial regions; moreover, this technique revealed that several PIs were specifically localized to cancer cell clusters. These PIs were heterogeneously distributed within cancer cell clusters, allowing us to identify two different populations of cancer cells that predominantly expressed either PI(18:0 ⁄ 18:1) or PI(18:0 ⁄ 20:3). Tracing the expression level of PIs during cancer cell progression suggested that the latter population is associated with the invasion. Our study documents a novel model for phospholipid analysis of breast cancer tissues by using high-resolution MALDI IMS and identifies candidate PIs that can describe a specific phenotype of cancer cells. (Cancer Sci 2013; 104: 1372-1379 S ince Warburg's report on the upregulation of glycolysis and the increase in lactate production in cancer cells, (1) cancer-related metabolic processes have been studied intensively.(2) In terms of lipid metabolism, de novo fatty acid synthesis is frequently upregulated in cancer cells, even in the early stages of cancer progression.(2,3) This "reprogramming" of lipid metabolism could be associated with the proliferation, membrane fluidity, and apoptosis of cancer cells by affecting membrane lipid remodeling.(3) Recent studies demonstrated the accumulation of several phospholipids in breast cancer tissues and their association with sex hormone receptor expression, tumor grade, and prognosis. (4,5) Mass spectrometry (MS) is often used to investigate phospholipid profiles in living materials, and MALDI is the common ionization technique used for MS analysis. Matrixassisted laser desorption ⁄ ionization imaging mass spectrometry (MALDI IMS) is a new modality that facilitates the acquisition of mass spectra directly from tissue specimens and provides reconstructed density maps of detected ions.(6) In contrast to conventional MS analysis, which requires lipid extraction, MALDI IMS does not destroy the histological structures of living materials, and the acquired mapping images can be compared with the corresponding histological images. (7) Consequently, MALDI ...

Caveolin-1 (Cav-1) has been extensively characterized in cancer biological research. However, the role of Cav-1 in the interaction between tumor and stromal cells remains unclear. In the present study, we examined Cav-1 expression in tumor cells and stromal cells in breast cancer tissue by immunohistochemical analysis and evaluated its prognostic value in a training cohort. Immunohistochemical analysis of Cav-1 expression was scored as (++), (+) or ()) according to the proportion of positively stained tumor cells (T) and stromal cells (S). Correlation analysis between tumor ⁄ stromal Cav-1 expression and clinicopathological parameters revealed that only T(++) Cav-1 status was positively associated with tumor size and histological nodal status (P = 0.019 and 0.021, respectively). Univariate analysis revealed that combined T(++) ⁄ S()) status was significantly correlated with unfavorable prognostic outcomes (P < 0.001). Multivariate analysis demonstrated that this combined status is an independent prognostic factor for primary breast cancer (P = 0.002). Clinical outcomes in different subgroups of breast cancer patients were also strictly dependent on this combined status (P < 0.05). The prognostic value of T(++) ⁄ S()) Cav-1 status was also validated in the testing cohort. Collectively, our data indicate that high Cav-1 expression in tumor cells and lack of this expression in stromal cells could help identify a particular subgroup of breast cancer patients with potentially poor survival. Further studies are required to understand the regulatory mechanism of Cav-1 in the tumor microenvironment. (Cancer Sci 2011; 102: 1590-1596

No abstract