Noninvasive Computed Tomography-Based Deep Learning Model Predicts In Vitro Chemosensitivity Assay Results in Pancreatic Cancer.

OBJECTIVES: We aimed to predict in vitro chemosensitivity assay results from computed tomography (CT) images by applying deep learning (DL) to optimize chemotherapy for pancreatic ductal adenocarcinoma (PDAC). MATERIALS AND METHODS: Preoperative enhanced abdominal CT images and the histoculture drug response assay (HDRA) results were collected from 33 PDAC patients undergoing surgery. Deep learning was performed using CT images of both the HDRA-positive and HDRA-negative groups. We trimmed small patches from the entire tumor area. We established various prediction labels for HDRA results with 5-fluorouracil (FU), gemcitabine (GEM), and paclitaxel (PTX). We built a predictive model using a residual convolutional neural network and used 3-fold cross-validation. RESULTS: Of the 33 patients, effective response to FU, GEM, and PTX by HDRA was observed in 19 (57.6%), 11 (33.3%), and 23 (88.5%) patients, respectively. The average accuracy and the area under the receiver operating characteristic curve (AUC) of the model for predicting the effective response to FU were 93.4% and 0.979, respectively. In the prediction of GEM, the models demonstrated high accuracy (92.8%) and AUC (0.969). Likewise, the model for predicting response to PTX had a high performance (accuracy, 95.9%; AUC, 0.979). CONCLUSIONS: Our CT patch-based DL model exhibited high predictive performance in projecting HDRA results. Our study suggests that the DL approach could possibly provide a noninvasive means for the optimization of chemotherapy.

Effect of geranylated dihydrochalcone from Artocarpus altilis leaves extract on Plasmodium falciparum ultrastructural changes and mitochondrial malate: Quinone oxidoreductase.

Nearly half of the world's population is at risk of being infected by Plasmodium falciparum, the pathogen of malaria. Increasing resistance to common antimalarial drugs has encouraged investigations to find compounds with different scaffolds. Extracts of Artocarpus altilis leaves have previously been reported to exhibit in vitro antimalarial activity against P. falciparum and in vivo activity against P. berghei. Despite these initial promising results, the active compound from A. altilis is yet to be identified. Here, we have identified 2-geranyl-2', 4', 3, 4-tetrahydroxy-dihydrochalcone (1) from A. altilis leaves as the active constituent of its antimalarial activity. Since natural chalcones have been reported to inhibit food vacuole and mitochondrial electron transport chain (ETC), the morphological changes in food vacuole and biochemical inhibition of ETC enzymes of (1) were investigated. In the presence of (1), intraerythrocytic asexual development was impaired, and according to the TEM analysis, this clearly affected the ultrastructure of food vacuoles. Amongst the ETC enzymes, (1) inhibited the mitochondrial malate: quinone oxidoreductase (PfMQO), and no inhibition could be observed on dihydroorotate dehydrogenase (DHODH) as well as bc1 complex activities. Our study suggests that (1) has a dual mechanism of action affecting the food vacuole and inhibition of PfMQO-related pathways in mitochondria.

Health economics-based verification of functional myocardial ischemia evaluation of stable coronary artery disease in Japan: A long-term longitudinal study using propensity score matching.

BACKGROUND: The procedural numbers and medical costs of percutaneous coronary intervention (PCI), mainly elective PCI, have been increasing in Japan. Owing to increased interest in the appropriateness of coronary revascularization, we conducted this medical economics-based evaluation of testing and diagnosis of stable coronary artery disease (CAD). METHODS AND RESULTS: We reviewed patients' medical insurance data to identify stable CAD patients who underwent coronary computed tomography angiography, cardiac single-photon emission computed tomography, coronary angiography, or fractional flow reserve. Subjects were divided into anatomical and functional evaluation groups according to the modality of testing, and background factors were matched by propensity score. The endpoints were major adverse cardiovascular events (MACE), life years (LYs), medical costs, and cost-effectiveness analysis (CEA). The observations were performed for 36 months. MACE, medical costs, and CEA of the functional group in the overall category were trending to be better than the anatomical group (MACE, P = .051; medical costs: 3,105 US$ vs 4,430 US$, P = .007; CEA: 2,431 US$/LY vs 2,902 US$/LY, P = .043). CONCLUSIONS: The functional evaluation approach improved long-term clinical outcomes and reduced cumulative medical costs. As a result, the modality composition of functional myocardial ischemia evaluation was demonstrated to offer superior cost-effectiveness in stable CAD.

Identification of 3,4-Dihydro-2H,6H-pyrimido[1,2-c][1,3]benzothiazin-6-imine Derivatives as Novel Selective Inhibitors of Plasmodium falciparum Dihydroorotate Dehydrogenase.

Plasmodium falciparum's resistance to available antimalarial drugs highlights the need for the development of novel drugs. Pyrimidine de novo biosynthesis is a validated drug target for the prevention and treatment of malaria infection. P. falciparum dihydroorotate dehydrogenase (PfDHODH) catalyzes the oxidation of dihydroorotate to orotate and utilize ubiquinone as an electron acceptor in the fourth step of pyrimidine de novo biosynthesis. PfDHODH is targeted by the inhibitor DSM265, which binds to a hydrophobic pocket located at the N-terminus where ubiquinone binds, which is known to be structurally divergent from the mammalian orthologue. In this study, we screened 40,400 compounds from the Kyoto University chemical library against recombinant PfDHODH. These studies led to the identification of 3,4-dihydro-2H,6H-pyrimido[1,2-c][1,3]benzothiazin-6-imine and its derivatives as a new class of PfDHODH inhibitor. Moreover, the hit compounds identified in this study are selective for PfDHODH without inhibition of the human enzymes. Finally, this new scaffold of PfDHODH inhibitors showed growth inhibition activity against P. falciparum 3D7 with low toxicity to three human cell lines, providing a new starting point for antimalarial drug development.

[A Case of Stage â £ Gastric Cancer with Para-Aortic Lymph Node Metastasis, and Multiple Liver, Lung, and Bone Metastases Leading to Conversion Therapy].

We report a case of unresectable gastric cancer with para-aortic lymph node metastasis, and multiple liver, lung, and bone metastases leading to conversion therapy. A 70s-year-old man visited previous doctor with epigastralgia. He was diagnosed as stage Ⅳ gastric cancer with para-aortic lymph node metastasis, and multiple liver, lung, and bone metastases by upper gastrointestinal endoscopy, contrast enhanced computer tomography(CT), and positron emission tomography(PET). After a regimen consisting of 6 courses of capecitabine plus cisplatin plus trastuzumab, para-aortic lymph node metastasis and liver, lung, and bone metastases were absent in CT and PET images. So, he visited our department for surgery treatment. We judged curative resection could be achieved for gastric cancer. Total gastrectomy, D2 and paraaortic lymphadenectomy, and cholecystectomy were performed. The histopathological examination of the resected specimen revealed the efficacy of chemotherapy was Grade 2b. The patient was discharge 14 days after the operation, and capecitabine plus trastuzumab was started as adjuvant chemotherapy, and the patient remains alive without recurrence 11 months after surgical treatment.

Identification and functional analysis of glutamine transporter in Streptococcus mutans.

BACKGROUND: Streptococcus mutans, a biofilm-forming bacterium, possesses several transporters that function as import/export molecules. Among them, the PII protein family is composed of members that regulate glutamine synthesis in bacterial species. OBJECTIVE: In this study, we characterized the function of the glutamine transporter in S. mutans MT8148. METHODS: The SMU.732 gene, corresponding to glnP in S. mutans, is homologous to the glutamine transporter gene in Bacillus subtilis. We constructed a glnP-inactivated mutant strain (GEMR) and a complement strain (comp-GEMR) and evaluated their biological functions. RESULTS: Growth of GEMR was similar in the presence and absence of glutamine, whereas the growth rates of MT8148 and comp-GEMR were significantly lower in the presence of glutamine as compared to its absence. Furthermore, biofilms formed by MT8148 and comp-GEMR were significantly thicker than that formed by GEMR, while the GEMR strain showed a significantly lower survival rate in an acidic environment than the other strains. Addition of n-phenyl-2-naphthylamine, used to label of the membrane, led to increased fluorescence intensity of MT8148 and GEMR, albeit that was significantly lower in the latter. CONCLUSIONS: These results suggest that glnP is associated with glutamine transport in S. mutans, especially the import of glutamine involved in biofilm formation.

[Improvement of QOL by Surgery in Two Patients for Brain Metastasis from Esophageal Carcinoma with Paralysis-A Report of Two Cases].

Brain metastasis from esophageal cancer is rare. Symptoms such as paralysis caused a decline in quality of life(QOL)and activity of daily life(ADL)and required emergency treatment. We report 2 cases in which QOL was improved by emergency resection for brain metastasis from esophageal carcinoma with paralysis. Case 1: A 50's male was diagnosed esophageal carcinoma and underwent esophagectomy(pT3N2M0, Stage Ⅲ). Brain metastasis was detected owing to development of left hemiparesis. Craniotomy and tumorectomy were performed, left hemiparesis was improved. He died 10 months after diagnosis of brain metastasis due to progression of other metastatic lesions. Case 2: A 61-year-old female was diagnosed esophageal carcinoma and underwent esophagectomy(pT3N1M0, Stage Ⅲ). She developed right hemiparesis 5 months after esophagectomy, admitted to our hospital. Brain and lung metastases were detected, craniotomy and tumorectomy and were performed, right hemiparesis was improved. Although systemic chemotherapy was administered, she died 10 months after diagnosis of brain metastasis due to progression of lung metastasis. Conclusion: Aggressive surgical treatments for brain metastasis were one good treatment option to maintain QOL and ADL.

[A Successfully Treated Patient Who Underwent Esophageal Bypass Surgery after Undergoing Stent Placement for Unresectable Advanced Esophageal Cancer Stenosed after CRT].

Esophageal bypass surgery is a treatment for oral ingestion in cases of unresectable esophageal cancer with esophageal stricture. Esophageal bypass surgery may be necessary especially in cases of advanced esophageal stricture after CRT because of the high risk of bleeding and perforation due to esophageal stent placement. In recent years, as a safe technique with fewer complications, esophageal bypass surgery using a Y-shaped gastric tube has been increasingly performed. Therefore, we will introduce cases that have undergone esophageal bypass surgery after undergoing stent placement for unresectable advanced esophageal cancer stenosed after CRT.

Perforated vesicles composed of amphiphilic diblock copolymer: new artificial biomembrane model of nuclear envelope.

With the aim of creating a new artificial model of a biomembrane for the nuclear envelope, perforated vesicles were prepared employing an amphiphilic diblock copolymer of poly(methacrylic acid)-block-poly(methyl methacrylate-random-methacrylic acid-random-2,2,6,6-tetramethyl-4-piperidyl methacrylate), PMAA-b-P(MMA-r-MAA-r-TPMA), by polymerization-induced self-assembly through photo nitroxide-mediated controlled/living radical polymerization (photo NMP). The photo NMP in an aqueous methanol solution produced spherical vesicles perforated with various holes and pores in the surface. The perforation of the vesicles was prevented by trifluoroacetic acid based on the disturbance of the MAA-TPMA interaction in the hydrophobic block chain. The investigation of the morphology changes by the polymerization progress revealed that the perforated spherical vesicles were produced within the membrane of contorted huge vesicles that were formed during the early stage of the polymerization due to the extension of the hydrophobic block chain. The perforated vesicles were found to show a reversible thermo-responsive behavior in the range of 25-50 °C based on dynamic light scattering and transmittance measurements. The vesicles were fused and divided into much smaller vesicles at high temperature, but were restored by cooling. However, the restored vesicles only had a few holes and no pores in the surface. The rearrangement of the MAA-TPMA interaction at high temperature produced more morphologically stable non-perforated vesicles.

Increase of Tumor Infiltrating γδ T-cells in Pancreatic Ductal Adenocarcinoma Through Remodeling of the Extracellular Matrix by a Hyaluronan Synthesis Suppressor, 4-Methylumbelliferone.

OBJECTIVES: Desmoplastic changes of extracellular matrix (ECM) containing large amounts of hyaluronan (HA) are of interest in chemo- and immunoresistance of pancreatic ductal adenocarcinoma (PDAC). The goal of this study was to evaluate the effects of 4-methylumbelliferone (MU), a selective inhibitor of HA, on ECM and to examine how MU affects adoptive immunotherapy. METHODS: The effect of MU on cell proliferation, HA synthesis and formation of ECM were investigated in four PDAC cell lines. In addition, the cytotoxicity of γδ T-cell-rich peripheral blood mononuclear cells (PBMCs) collected from healthy donors and stimulated with zoledronate and interleukin-2 was examined in the presence of MU. The amount of HA and tumor-infiltrating lymphocytes were also investigated in mice xenograft models. RESULTS: In vitro, 1.0 mM MU inhibited cell proliferation by 45-70% and HA synthesis by 55-80% in all four PDAC cell lines, and enhanced γδ T-cell-rich PBMC-mediated cytotoxicity against PDAC cells. In vivo, MU reduced intratumoral HA and promoted infiltration of inoculated γδ T-cells into tumor tissue, and consequently suppressed tumor growth. CONCLUSIONS: 4-methylumbelliferone may be an effective immunosensitizer against PDAC through induction of structural changes in the ECM.

4-Methylumbelliferone Decreases the Hyaluronan-rich Extracellular Matrix and Increases the Effectiveness of 5-Fluorouracil.

BACKGROUND/AIM: Pancreatic cancer responds poorly to most chemotherapeutic agents. Several studies have reported that hyaluronan (HA)-rich extracellular matrix (ECM) is a biological barrier against chemotherapeutic agents. 4-methylumbelliforone (MU) led to inhibition of HA synthesis and its preservation in ECM, which may enhance 5-fluorouracil (5-FU) cytotoxicity. Thus, new therapy with MU and 5-FU may be developed for pancreatic cancer. MATERIALS AND METHODS: A 5-fluorouracil (5-FU) concentration and 4-methylumbelliferone (MU) dosage was analyzed by high-performance liquid chromatography (HPLC). Change in antitumor efficacy of 5-FU in combination with MU was also examined in vivo and in vitro. RESULTS: Combined 5-FU and MU treatment inhibited cell proliferation better than 5-FU alone; 0.01 mM 5-FU alone decreased cell proliferation by 37.7 %, while 0.01 mM 5-FU with 0.5 mM MU decreased cell proliferation by 57.4%. MU enhanced the intracellular concentration of 5-FU by 47.3% compared to control. Mice tumors treated with 5-FU and MU decreased in size and animal survival was prolonged. Moreover, MU decreased cohesiveness of the intercellular space. CONCLUSION: Combination therapy of 5-FU with MU was effective. A novel therapy can be designed for pancreatic cancer by using ECM modulation.

Impact of Indoxyl Sulfate on Coronary Plaques in Patients on Hemodialysis.

Serum indoxyl sulfate (IS; a uremic toxin) levels, which are significantly higher in patients with chronic kidney disease, including those undergoing hemodialysis, than in the robust, are associated with both cardiovascular disease (CVD) and CVD-related mortality. Furthermore, coronary artery calcium (CAC) is an independent predictor of cardiovascular events in patients undergoing hemodialysis. This study aimed to interpret the association between serum IS levels and coronary plaque burden (CPB) or CAC.A total of 30 consecutive patients on hemodialysis, who underwent 320-row coronary multidetector computed tomography (MDCT) angiography for suspected coronary artery disease, were enrolled in this prospective study. Coronary artery percent atheroma volume (a CPB marker) and percent calcium volume (a CAC marker) assessed using MDCT were evaluated. Furthermore, various oxidative and inflammatory markers typified by serum IS levels at a dialysis-free day were measured. Using these data, we investigated correlation between the inflammatory marker IS and CPB or CAC.Multivariable analysis indicated that serum IS levels were positively correlated with CAC [partial regression coefficient, 2.89; 95% confidence interval (CI), 0.35-5.43; P = 0.03] but not with CPB, even after adjustment for cofounders. Composite cardiovascular events, namely, as all-cause death, non-fatal myocardial infarction, disabling stroke, and hospital admission for other cardiovascular events, were reported to be 50% in all patients (95% CI, 32.1-67.9).In patients undergoing hemodialysis, serum IS levels were significantly associated with CAC but not with CPB.

Application of 80-kVp scan and raw data-based iterative reconstruction for reduced iodine load abdominal-pelvic CT in patients at risk of contrast-induced nephropathy referred for oncological assessment: effects on radiation dose, image quality and renal function.

OBJECTIVE: To evaluate the image quality, radiation dose, and renal safety of contrast medium (CM)-reduced abdominal-pelvic CT combining 80-kVp and sinogram-affirmed iterative reconstruction (SAFIRE) in patients with renal dysfunction for oncological assessment. METHODS: We included 45 patients with renal dysfunction (estimated glomerular filtration rate  <45 ml per min per 1.73 m2) who underwent reduced-CM abdominal-pelvic CT (360 mgI kg-1, 80-kVp, SAFIRE) for oncological assessment. Another 45 patients without renal dysfunction (estimated glomerular filtration rate >60 ml per lmin per 1.73 m2) who underwent standard oncological abdominal-pelvic CT (600 mgI kg-1, 120-kVp, filtered-back projection) were included as controls. CT attenuation, image noise, and contrast-to-noise ratio (CNR) were compared. Two observers performed subjective image analysis on a 4-point scale. Size-specific dose estimate and renal function 1-3 months after CT were measured. RESULTS: The size-specific dose estimate and iodine load of 80-kVp protocol were 32 and 41%,, respectively, lower than of 120-kVp protocol (p < 0.01). CT attenuation and contrast-to-noise ratio of parenchymal organs and vessels in 80-kVp images were significantly better than those of 120-kVp images (p < 0.05). There were no significant differences in quantitative or qualitative image noise or subjective overall quality (p > 0.05). No significant kidney injury associated with CM administration was observed. CONCLUSION: 80-kVp abdominal-pelvic CT with SAFIRE yields diagnostic image quality in oncology patients with renal dysfunction under substantially reduced iodine and radiation dose without renal safety concerns. Advances in knowledge: Using 80-kVp and SAFIRE allows for 40% iodine load and 32% radiation dose reduction for abdominal-pelvic CT without compromising image quality and renal function in oncology patients at risk of contrast-induced nephropathy.

[A Case of Advanced Gastric Cancer with Peritoneal Dissemination after Gastrectomy Effectively Treated with Combination Chemotherapy of Ramucirumab and Paclitaxel].

The REGARD and RAINBOW trials revealed the effectiveness of ramucirumab(RAM)for advanced gastric cancer patients who had been previously treated with chemotherapy. In the latest Japanese gastric cancer treatment guidelines, PAM plus paclitaxel(PTX)was positioned as a second-line chemotherapy for advanced gastric cancer. We report a case of advanced gastric cancer with peritoneal dissemination after gastrectomy effectively treated with RAM plus PTX. A 66-year-old woman underwent total gastrectomy with D2 lymph node dissection, splenectomy, and distal pancreatectomy. The pathological diagnosis was poorly differentiated adenocarcinoma, pT4b(pancreas), N3b, P1, CY1, Stage Ⅳ. She was treated with postoperative chemotherapy of S-1 plus cisplatin. However, 5 months after surgery, computed tomography(CT)showed ascites and recurrence of peritoneal dissemination. Cytological examination showed adenocarcinoma cells in the ascites. She was treated with combination chemotherapy of RAM and PTX as second line chemotherapy. After 1 course of this therapy, CT revealed complete disappearance of ascites and significant reduction in the size of the peritoneal dissemination. The patient survived without progression for 8 months after the recurrence was detected.

[A Case of Perforated Gastric Cancer Treated with Curative Resection Following Conservative Medical Management and Chemotherapy].

Perforated gastric cancer typically requires life-saving emergency surgery. However, preoperative diagnosis is difficult, the rate of radical resection is low, and the prognosis remains poor. Perforated gastric cancer is generally treated with 1- or 2- stage gastrectomy, but radical resection is rarely performed after a conservative medical management and chemotherapy for perforated gastric cancer. A 65-year-old man visited another hospital with left upper abdominal pain. He was diagnosed with upper GI perforation, and conservative medical management was selected because peritonitis was limited. After close examination, a Type 3 tumor was found in the cardiac region of the stomach. As the advanced gastric cancer was unresectable, chemotherapy, comprising4 courses of SP plus T-mab, was subsequently administered. As the therapeutic effect was PR, we performed total gastrectomy. The pathological findings were tub2>tub1>por2: pT2N1CY0H0P0M0, pStageⅡ, and we achieved curative resection. Postoperatively, S-1 treatment was performed as an adjuvant chemotherapy. The patient remains alive, without recurrence, for 3 years and 6 months postoperatively.

[A Case of Laparoscopic Resection for Locally Advanced Primary Rectal Cancer after Neoadjuvant Chemotherapy].

We treateda 70-year-oldfemale patient with locally advancedrectal cancer accompaniedby metastases to other organs. Three courses of S-1 plus oxaliplatin(SOX)therapy were administered as neoadjuvant chemotherapy(NAC), andthe cancer was subsequently treatedwith laparoscopic rectal resection. She hadvisiteda physician with a chief complaint of melena. A type 2 tumor located in the rectum Rb was found during the lower gastrointestinal endoscopy, which was diagnosed as an adenocarcinoma by biopsy. Vaginal invasion andlymph node metastasis were observedon CT andMRI. After 3 courses of SOX therapy(NAC), her condition was categorized as SD. Laparoscopic rectal amputation(D3)combinedwith resection of the ovary, uterus, and vagina was performed. On histopathological examination, the tumor was an adenocarcinoma, muc> tub2, ypT4b(AI, vaginal wall), int, INF b, ly1, v2, EX(-), PN1a, grade 1, pPM0, pDM0, pRM0 and pStage Ⅲa. The histological analysis demonstrated that the therapeutic effect of chemotherapy was grade 1a. Laparoscopic surgery, which is a relatively safe procedure, may be useful after NAC for an R0 resection.

4-Methylumbelliferone Suppresses Hyaluronan Synthesis and Tumor Progression in SCID Mice Intra-abdominally Inoculated With Pancreatic Cancer Cells.

OBJECTIVES: Pancreatic ductal adenocarcinoma contains large amounts of the glycosaminoglycan hyaluronan (HA), which is involved in various physiological processes. Here, we aimed to clarify the anticancer mechanisms of 4-methylumbelliferone (MU), a well-known HA synthesis inhibitor. METHODS: MIA PaCa-2 human pancreatic cancer cells were used. We evaluated cellular proliferation, migration, and invasion in the presence of MU, exogenous HA, and an anti-CD44 antibody. We also analyzed apoptosis, CD44 expression, and HA-binding ability using flow cytometry. The HA content in tumor tissue was quantified and histopathologically investigated in mice who had been inoculated with cancer cells. RESULTS: In vitro, MU inhibited pericellular HA matrix formation; however, HAS3 mRNA was up-regulated. Treatment with 0.5 mM MU suppressed cellular proliferation by 26.4%, migration by 14.7%, and invasion by 22.7%. Moreover, MU also significantly increased apoptosis. CD44 expression and HA-binding ability were not altered by MU. In vivo, MU suppressed HA accumulation in pancreatic tumors and improved survival times in tumor-bearing mice. CONCLUSIONS: 4-Methylumbelliferone indirectly caused apoptosis in pancreatic cancer cells by inhibiting HA production. 4-Methylumbelliferone may be a promising agent in the treatment of pancreatic cancer.

Antitumor effects of the hyaluronan inhibitor 4-methylumbelliferone on pancreatic cancer.

Hyaluronan (HA) is a major component of the extracellular matrix (ECM), and influences tumor invasion and metastasis. In a previous study, the present authors reported for the first time that 4-methylumbelliferone (MU) inhibited HA synthesis and suppressed tumor growth. However, the localization of HA and the changes in ECM morphology caused by MU in pancreatic cancer remain to be examined in detail. In the present study, the cytotoxicity of MU and its effect on cellular proliferation was evaluated in the human pancreatic cancer cell line MIA PaCa-2. The amount of HA synthesized and the retention of HA around the cells were quantitatively and immunohistochemically analyzed in vitro and in vivo. Structural changes in the ECM in the tumor tissue were investigated using an electron microscope. MU treatment led to a decrease in extracellular HA retention, as evidenced by a particle exclusion assay and immunohistochemical staining. Cell proliferation was suppressed by MU in a dose-dependent manner. The release of lactate dehydrogenase into the culture medium due to damage to the cellular membrane did not increase following MU administration. In tumor-inoculated mice, MU suppressed any increase in tumor volume and decreased the quantity of HA. Electron microscopy revealed that MU attenuated the intercellular space and caused it to be less cohesive. These data indicate that MU inhibits HA synthesis and reduces the amount of HA in the ECM while exhibiting no obvious cytotoxic effect. These findings suggest that MU has potential as a novel therapeutic agent for pancreatic cancer.

A new histological therapeutic classification system to predict eradicated and residual lymph nodes in breast cancer after neoadjuvant chemotherapy.

The indication for neoadjuvant chemotherapy (NAC) has recently broadened to include its use in the treatment of initial stage breast cancer. Axillary lymph node metastasis after NAC in breast cancer is a poor prognostic factor. Thus, the prediction of lymph node metastasis is important to estimate the prognosis of breast cancer patients after NAC. Therefore, we focused on residual carcinoma patterns of primary breast tumors after NAC and examined the correlation between the patterns and lymph node metastasis. In this study, we examined 50 breast cancer specimens and associated dissected lymph nodes after NAC. We divided 40 cases into an eradicated lymph node group and a residual lymph node group to analyze residual carcinoma patterns of primary breast tumors. Residual carcinoma patterns were classified according to the cell density of carcinoma cells: dense, focal/nested and sporadic/in-situ. There were significant differences in residual carcinoma patterns (P<0.01) among the three pattern groups. There was a high incidence of dense patterns in the residual lymph node group and a high incidence of sporadic/in-situ patterns in the eradicated lymph node group. Analysis of residual carcinoma patterns of primary breast tumors and clinicopathological factors demonstrated that there were significant differences in tumor reduced ratio on CT (P<0.001), primary tumor area before NAC (P<0.01), primary tumor area after NAC (P<0.00001), intrinsic subtype (P<0.01), Ki-67 labeling index (P<0.01), histological grade (P<0.05) and mitotic count (P<0.01) between the dense and non-dense groups. Therefore, our results suggest that the residual carcinoma pattern is useful for predicting eradicated or residual lymph nodes and the malignant potential in breast cancer after NAC.

Patterned Co-culture of Live Cells on a Microchip by Photocrosslinking with Benzophenone.

The patterned coculture of different types of living cells in a microfluidic device is crucial for the analysis of cellular interactions and cell-cell communication. In the present study, cell patterning was achieved by photocrosslinking benzophenone derivatives in a microfluidic channel. Optimization of UV irradiation conditions enabled successful fixation of live cells. In addition, patterning and co-culture of non-adherent K562 cells and adherent RF-6A cells was achieved by successive rounds of patterning. The present approach is expected to be useful for the development of in vitro methods for studying cell signaling.