Gel-Free 3D Tumoroids with Stem Cell Properties Modeling Drug Resistance to Cisplatin and Imatinib in Metastatic Colorectal Cancer

Researchers have developed several three-dimensional (3D) culture systems, including spheroids, organoids, and tumoroids with increased properties of cancer stem cells (CSCs), also called cancer-initiating cells (CICs). Drug resistance is a crucial issue involving recurrence in cancer patients. Many studies on anti-cancer drugs have been reported using 2D culture systems, whereas 3D cultured tumoroids have many advantages for assessing drug sensitivity and resistance. Here, we aimed to investigate whether Cisplatin (a DNA crosslinker), Imatinib (a multiple tyrosine kinase inhibitor), and 5-Fluorouracil (5-FU: an antimetabolite) alter the tumoroid growth of metastatic colorectal cancer (mCRC). Gene expression signatures of highly metastatic aggregative CRC (LuM1 cells) vs. low-metastatic, non-aggregative CRC (Colon26 and NM11 cells) were analyzed using microarray. To establish a 3D culture-based multiplexing reporter assay system, LuM1 was stably transfected with the Mmp9 promoter-driven ZsGreen fluorescence reporter gene, which was designated as LuM1/m9 cells and cultured in NanoCulture Plate®, a gel-free 3D culture device. LuM1 cells highly expressed mRNA encoding ABCG2 (a drug resistance pump, i.e., CSC/CIC marker), other CSC/CIC markers (DLL1, EpCAM, podoplanin, STAT3/5), pluripotent stem cell markers (Sox4/7, N-myc, GATA3, Nanog), and metastatic markers (MMPs, Integrins, EGFR), compared to the other two cell types. Hoechst efflux stem cell-like side population was increased in LuM1 (7.8%) compared with Colon26 (2.9%), both of which were markedly reduced by verapamil treatment, an ABCG2 inhibitor. Smaller cell aggregates of LuM1 were more sensitive to Cisplatin (at 10 μM), whereas larger tumoroids with increased ABCG2 expression were insensitive. Notably, Cisplatin (2 μM) and Imatinib (10 μM) at low concentrations significantly promoted tumoroid formation (cell aggregation) and increased Mmp9 promoter activity in mCRC LuM1/m9, while not cytotoxic to them. On the other hand, 5-FU significantly inhibited tumoroid growth, although not completely. Thus, drug resistance in cancer with increased stem cell properties was modeled using the gel-free 3D cultured tumoroid system. The tumoroid culture is useful and easily accessible for the assessment of drug sensitivity and resistance

UV エンドヌクレアーゼ オ ケッソン シタ ブンレツ コウボ ニオケル シガイセン ソンショウ ミトコンドリア DNA ノ シュウフク

P(論文)departmental bulletin pape

Depletion of Lipid Efflux Pump ABCG1 Triggers the Intracellular Accumulation of Extracellular Vesicles and Reduces Aggregation and Tumorigenesis of Metastatic Cancer Cells

The ATP-binding cassette transporter G1 (ABCG1) is a cholesterol lipid efflux pump whose role in tumor growth has been largely unknown. Our transcriptomics revealed that ABCG1 was powerfully expressed in rapidly metastatic, aggregative colon cancer cells, in all the ABC transporter family members. Coincidently, genetic amplification of ABCG1 is found in 10–35% of clinical samples of metastatic cancer cases. Expression of ABCG1 was further elevated in three-dimensional tumoroids (tumor organoids) within stemness-enhancing tumor milieu, whereas depletion of ABCG1 lowered cellular aggregation and tumoroid growth in vitro as well as hypoxia-inducible factor 1α in cancer cells around the central necrotic areas in tumors in vivo. Notably, depletion of ABCG1 triggered the intracellular accumulation of extracellular vesicles (EVs) and regression of tumoroids. Collectively, these data suggest that ABCG1 plays a crucial role in tumorigenesis in metastatic cancer and that depletion of ABCG1 triggers tumor regression with the accumulation of EVs and their derivatives and cargos, implicating a novel ABCG1-targeting therapeutic strategy by which redundant and toxic substances may be accumulated in tumors leading to their regression

Clinical Evaluation of Complex Decongestive Physiotherapy for Acute Malignant Lymphedema of the Leg

癌終末期における下肢浮腫は難治性であり,浮腫増悪により歩行困難となる場合が少なくない.今回,入院中に下肢リンパ浮腫を発症した症例に対し複合的理学療法を施行しその効果を検討した.対象は,当院緩和ケアチームで担当した急性下肢リンパ浮腫症例のうち,浮腫発症前Performance Status(以下PS)2以上の症例10例を対象とした.下肢リンパ浮腫の診断は,理学所見とともに超音波検査を行い静脈血栓が併存していないことを確認した.複合的理学療法としてスキンケア,リンパドレナージ,圧迫療法,運動療法を組み合わせて治療.浮腫軽減の目的での利尿剤の投与は併用しなかった.治療効果の検討のため,下肢計測(足背,足関節,下腿,大腿周径),PS変化で有効性を検討した.治療による副作用・事故はなく安全に治療を行えた.下肢計測では4回の治療で有意に大腿,下腿周径の改善を認めた.PSは治療前平均3.8で歩行困難であったが,治療開始7日で平均PS1.9と有意に改善し,さらに21日後では,治療により歩行可能となり平均PS0.9に改善された.以上より,下肢リンパ浮腫の治療は困難であるが,PS2以上で合併症のない急性期では複合的理学療法によりPSが改善され有効な治療法と考えられる.Malignant lymphedema of the leg is intractable : although not fatal, the patients\u27 quality of life and daily life activity can be decreased. This study reports the usefulness of complex decongestive physiotherapy (CDP) as a treatment for acute malignant lymphedema. Ten cases of acute malignant lymphedema with pre-critical Performance Status greater than 2 were treated with CDP by the palliative care team in Nakadori General Hospital. Diagnosis of acute malignant lymphedema was determined from clinical history and physical examination. Furthermore, ultra-sonography examination was performed to rule out the possibility of deep venous thrombosis. CDP was structured by Dr Michael Foeldi as multiple treatments of skin care, manual lymph drainage (MLD), compression bandage and ergotherapy. The effectiveness of CDP was evaluated through changes in body weight, leg diameter, serum albumin value and performance status (PS). No side effects were observed during CDP. There were no changes in body weight and serum albumin value. Significant improvement of leg diameter was observed at the fourth treatment. PS was significantly improved seven days after CDP from 3.8 to 1.9, and with continuous treatment, by the 21st day PS improved to 0.9 and the patients could walk around the bedside. Although treatment of acute malignant leg lymphedema is problematic, CDP is an effective treatment when applied as soon as possible