Secretory autophagy-promoted cargo exocytosis requires active RAB37.

RAB37 GTPase regulates cargo exocytosis by cycling between an inactive GDP-bound form and an active GTP-bound form. We reveal that RAB37 simultaneously regulates autophagy activation and tissue inhibitor of metalloproteinase 1 (TIMP1) secretion in lung cancer cells under starvation conditions. TIMP1, an inflammatory cytokine, is a known inhibitory molecule of matrix metalloproteinases matrix metalloproteinase 9 and suppresses the mobility of lung cancer cells both in vitro and in vivo through conventional exocytosis under serum-free conditions. Notably, we disclosed that secretory autophagy participates in TIMP1 secretion in a RAB37- and Sec22b-dependent manner. Sec22b, a SNARE family protein, participates in vesicle and membrane fusion of secretory autophagy. Knockdown of Sec22b decreased TIMP1 secretion and cell motility but did not affect cell proliferation under starvation conditions. We confirmed that starvation-activated RAB37 accompanied by Sec22b is essential for secretory autophagy to further enhance TIMP1 exocytosis. We further use an off-label drug amiodarone to demonstrate that autophagy induction facilitates TIMP1 secretion and suppresses the motility and metastasis of lung cancer cells in a RAB37-dependent manner in the lung-to-lung mouse model. In conclusion, we demonstrated that the RAB37 activation plays a pivotal regulatory role in secretory autophagy for TIMP1 secretion in lung cancer.Abbreviations: ATG: autophagy-related gene; GDP: guanosine diphosphate; GTP: guanosine triphosphate; LC3: microtubule-associated protein 1A/1B-light chain 3; SNARE: soluble N-ethylmaleimide-sensitive-factor attachment protein receptor; TIMP1: tissue inhibitor matrix metalloproteinase 1.

Autophagy Upregulates miR-449a Expression to Suppress Progression of Colorectal Cancer.

Many studies reported that microRNAs (miRNAs) target autophagy-related genes to affect carcinogenesis, however, autophagy-deficiency-related miRNA dysfunction in cancer development remains poorly explored. During autophagic progression, we identified miR-449a as the most up-regulated miRNA. MiR-449a expression was low in the tumor parts of CRC patient specimens and inversely correlated with tumor stage and metastasis with the AUC (area under the curve) of 0.899 and 0.736 as well as poor overall survival rate, indicating that miR-449a has the potential to be a prognostic biomarker. In the same group of CRC specimens, low autophagic activity (low Beclin 1 expression and high p62 accumulation) was detected, which was significantly associated with miR-449a expression. Mechanistic studies disclosed that autophagy upregulates miR-449a expression through degradation of the coactivator p300 protein which acetylates the transcription factor Forkhead Box O1 (FoxO1). Unacetylated FoxO1 translocated to the nucleus and bound to the miR-449a promoter to drive gene expression. Either activation of autophagy by the inducer or overexpression of exogenous miR-449a decreases the expression of target gene LEF-1 and cyclin D1, which lead to decreased proliferation, colony formation, migration, and invasion of CRC cells. Autophagy-miR-449a-tartet genes mediated suppression of tumor formation was further confirmed in the xenograft mouse model. In conclusion, this study reveals a novel mechanism wherein autophagy utilizes miR-449a-LEF1-cyclin D1 axis to suppress CRC tumorigenesis. Our findings open a new avenue toward prognosis and treatment of CRC patients by manipulating autophagy-miR-449a axis.

Tomar leche no siempre es bueno. .. un accidente que a todos nos puede suceder / Drinking milk is not always good ... ... an accident that can happen to all of us

En pacientes que se presentan con disfagia y/o odinofagia súbitas después de ingerir alimentos, debemos sospechar la ingestión de un cuerpo extraño. Los cuerpos extraños en esófago no siempre son visibles en una radiografía de cuello, por lo que debemos utilizar otros métodos diagnósticos como la tomografía axial computarizada y la gastroscopía. El presente caso ilustra la ingestión accidental del sello de un envase de leche.

In patients acute with dysphagia and/or odynophagia after ingestión of a meal, we should always suspect the ingestion of a foreign body. Esophageal foreign bodies are not always visible on X-rays and we must rely on other diagnostic methods like CT scan and endoscopy. This case ilustrates the accidental ingestion of the seal of a milk carton.

Autophagy-preferential degradation of MIR224 participates in hepatocellular carcinoma tumorigenesis.

Autophagy and microRNA (miRNA) are important regulators during cancer cell tumorigenesis. Impaired autophagy and high expression of the oncogenic microRNA MIR224 are prevalent in hepatocellular carcinoma (HCC); however, the relationship between the 2 phenomena remains elusive. In this study, we are the first to reveal that autophagy selectively regulates MIR224 expression through an autophagosome-mediated degradation system. Based on this finding, we further demonstrated that in hepatitis B virus (HBV)-related HCC, aberrant autophagy (low autophagic activity) results in accumulation of MIR224 and decreased expression of the target gene Smad4, which leads to increased cell migration and tumor formation. Preferential recruitment of MIR224 into the autophagosome was clearly demonstrated by a) miRNA in situ hybridization under confocal microscopy, and b) immunogold labeling of MIR224 under electron microscopy compared with a ubiquitously expressed microRNA MIRlet7e/let-7. Furthermore, we found that off-label use of amiodarone, an antiarrhythmic agent, effectively suppressed HCC tumorigenesis through autophagy-mediated MIR224 degradation both in vitro and in vivo. In summary, we identified amiodarone as a new autophagy inducer, which may provide an alternative approach in HCC therapy through a novel tumor suppression mechanism.

Autophagy suppresses tumorigenesis of hepatitis B virus-associated hepatocellular carcinoma through degradation of microRNA-224.

UNLABELLED: In hepatocellular carcinoma (HCC), dysregulated expression of microRNA-224 (miR-224) and impaired autophagy have been reported separately. However, the relationship between them has not been explored. In this study we determined that autophagy is down-regulated and inversely correlated with miR-224 expression in hepatitis B virus (HBV)-associated HCC patient specimens. These results were confirmed in liver tumors of HBV X gene transgenic mice. Furthermore, miR-224 was preferentially recruited and degraded during autophagic progression demonstrated by real-time polymerase chain reaction and miRNA in situ hybridization electron microscopy after extraction of autophagosomes. Our in vitro study demonstrated that miR-224 played an oncogenic role in hepatoma cell migration and tumor formation through silencing its target gene Smad4. In HCC patients, the expression of low-Atg5, high-miR-224, and low-Smad4 showed significant correlation with HBV infection and a poor overall survival rate. Autophagy-mediated miR-224 degradation and liver tumor suppression were further confirmed by the autophagy inducer amiodarone and miR-224 antagonist using an orthotopic SD rat model. CONCLUSION: A noncanonical pathway links autophagy, miR-224, Smad4, and HBV-associated HCC. These findings open a new avenue for the treatment of HCC.

Successfully seal pancreatic end after thermal distal pancreatectomy using needle arrays in alternating electromagnetic fields.

BACKGROUND: Pancreatic fistula is still the major postoperative morbidity after distal pancreatectomy (DP). An inductive heat technology via needle arrays in a system of alternating magnetic fields (AMFs) was designed to seal off the pancreatic end. METHODS: Twenty Lanyu pigs were divided into 2 groups for DP: the conventional group had hand-sewn closure of the pancreatic end (n = 10), and the AMF group received thermal DP by AMF (n = 10). Pathological examinations of the resected and remnant pancreas were studied immediately after resection and on the 14th postoperative day (POD), respectively. The severity and the incidence of pancreatic abscess were compared. RESULTS: The incidence and severity of pancreatic abscess were significantly decreased in the AMF group than those in the conventional group (P = .009). In the immediate postoperative period, microscopic examination of the pancreatic resected end showed prominent coagulative necrosis, loss of NADPH-diaphorase activity, and significant apoptosis at the resected pancreas in the AMF group compared with the control group. Fourteen days after AMF ablation, the pancreatic stump end was covered with thick fibrosis, and histological study of the remnant pancreas showed that the parenchyma had well recovered with positive NADPH-diaphorase activity, and the pancreatic duct was sealed off successfully by prominent periductal fibrosis and intraductal plug. The body weight gain on the 14th POD was significantly increased in the AMF group (from 23.8 ± 1.8 kg to 25.4 ± 5.5 kg) compared with the conventional group (from 25.3 ± 2.1 to 25.4 ± 6.0 kg; P = .003). CONCLUSIONS: Inductive heats by the AMF system via needle array can be performed easily and can seal the pancreatic cut surface well during DP.

Partial splenectomy using an electromagnetic thermal surgery system in a porcine model.

PURPOSE: Partial splenectomy is technically more complicated than total splenectomy due to difficulty in haemostasis, but it can preserve splenic function after operation. We evaluated the feasibility and safety of partial splenectomy performed by an electromagnetic thermal surgery system in a porcine model. METHODS: Our system was comprised of an alternating electromagnetic field generator, an extensible coil applicator, comb-needle arrays, and a temperature feedback control component. Ten Lanyu pigs were anaesthetised to conduct partial splenectomy. Two rows of comb-like stainless-steel needle arrays were inserted into the tissue at 15 cm from the distal tip of the spleen. The temperature of the tissues around the needle arrays was raised to 150°C for 3 min and the spleen was transected directly between the needle arrays and then sent for histological examination. Two weeks later, the animals underwent a second celiotomy to remove the remaining spleen for histological examination. RESULTS: The average duration of the partial splenectomy was 10 min as timed from insertion of the needle arrays to the transection of the spleen. There was no blood loss during the procedure. The cut surface of the spleen was well coagulated without any oozing sites. During the re-exploration, no intra-abdominal blood was found. There were dense adhesions between the spleen and the surrounding organs. Histological examination of the cut surface of the excised portion of the spleen showed coagulative necrosis with clot formation in the blood vessels. CONCLUSIONS: Partial splenectomy using our electromagnetic thermal system can achieve effective haemostasis and is safe and easy to perform.

Ras-related tumorigenesis is suppressed by BNIP3-mediated autophagy through inhibition of cell proliferation.

Autophagy plays diverse roles in Ras-related tumorigenesis. H-ras(val12) induces autophagy through multiple signaling pathways including Raf-1/ERK pathway, and various ERK downstream molecules of autophagy have been reported. In this study, Bcl-2/adenovirus E1B 19-kDa-interacting protein 3 (BNIP3) is identified as a downstream transducer of the Ras/Raf/ERK signaling pathway to induce autophagy. BNIP3 was upregulated by H-ras(val12) at the transcriptional level to compete with Beclin 1 for binding with Bcl-2. H-ras(val12)-induced autophagy suppresses cell proliferation demonstrated both in vitro and in vivo by expression of ectopic BNIP3, Atg5, or interference RNA of BNIP3 (siBNIP3) and Atg5 (shAtg5) using mouse NIH3T3 and embryo fibroblast cells. H-ras(val12) induces different autophagic responses depending on the duration of Ras overexpression. After a short time (48 hours) of Ras overexpression, autophagy inhibits cell proliferation. In contrast, a longer time (2 weeks) of Ras overexpression, cell proliferation was enhanced by autophagy. Furthermore, overexpression of mutant Ras, BNIP3, and LC3-II was detected in bladder cancer T24 cells and the tumor parts of 75% of bladder cancer specimens indicating a positive correlation between autophagy and tumorigenesis. Taken together, our mouse model demonstrates a balance between BNIP3-mediated autophagy and H-ras(val12)-induced tumor formation and reveals that H-ras(val12) induces autophagy in a BNIP3-dependent manner, and the threshold of autophagy plays a decisive role in H-ras(val12)-induced tumorigenesis. Our findings combined with others' reports suggest a new therapeutic strategy against Ras-related tumorigenesis by negative or positive regulation of autophagic activity, which is determined by the level of autophagy and tumor progression stages.

Electromagnetic thermoablation to treat thrombocytopenia in cirrhotic and hypersplenic rats.

BACKGROUND AND AIM: Thrombocytopenia due to hypersplenism is usually a serious condition in cirrhotic patients who have undergone invasive procedures. We designed a new treatment method using a high-frequency alternating electromagnetic force to treat the disease condition in a rat model. METHODS: Sprague-Dawley rats were given thioacetamide in drinking water and injected with methylcellulose intraperitoneally to create a cirrhotic hypersplenism model. Spleen volume was determined using the Carlson method. The Control Group consisted of 14 rats, 15 weeks old, that were used to determine the normal platelet count and normal spleen size. Experimental Group I, consisting of 15 rats, received electromagnetic thermoablation of their spleens, after which the spleen was returned to the abdomen. Group II consisted of 13 rats, receiving the same electromagnetic thermoablation as Group I, but the ablated portion was removed. Group III consisted of 14 rats receiving total splenectomies. RESULTS: Cirrhotic hypersplenism was confirmed during laparotomy and pathological examination. Spleen volume enlarged from 1513 +/- 375 mm(3) (Control Group) to 7943 +/- 2822 mm(3) (experimental groups). Platelet counts increased from 0.35 +/- 0.21 x 10(6)/mm(3) to 0.87 +/- 0.24 x 10(6)/mm(3) for Group I, from 0.52 +/- 0.23 x 10(6)/mm(3) to 1.10 +/- 0.20 x 10(6)/mm(3) for Group II, and from 0.47 +/- 0.23 x 10(6)/mm(3) to 1.18 +/- 0.26 x 10(6)/mm(3) for Group III. No rats died due to the treatment in any of the experimental groups. CONCLUSIONS: Our animal model performed successfully and our proposed electromagnetic thermotherapy effectively treated thrombocytopenia due to cirrhotic hypersplenism.

Electromagnetic thermal surgery system for liver resection: an animal study.

PURPOSE: Electromagnetic thermal surgery is a new technique. It applies an electrical current through coils to generate a high frequency magnetic field to heat up magnetic materials in the targeted area. Using this technique, we aim to perform liver resection without bleeding in rats and rabbits. MATERIALS AND METHODS: The electromagnetic machine can produce a high frequency magnetic field, with an input of 220 V-55 A-60 Hz, an output frequency of 62.1 kHz, and a power of 2.2 kW. The magnetic materials used in this study were fine needles made of stainless steel. For ex vivo experiments, we used porcine liver explants; in the animal model, sixteen Sprague-Dawley rats and seven New Zealand White rabbits were used. We inserted one needle array along the attempted resection lines and then used the magnetic coils to heat up the needles for three min. After heating, we resected the designated liver portions using surgical scalpels. RESULTS: In the ex vivo test, the fine needles were heated up effectively to achieve tissue coagulation (more than 90 degrees C). In the animal model the liver resection was performed without bleeding and no bile peritonitis was observed after the surgery. All animals were alive after the surgery until the end of the experiment (30 days). CONCLUSIONS: The experiments showed that our thermal surgery system is very effective in performing bloodless liver resection without further ligation or embolisation needed. Our technique is new and the system has great potential to develop into clinical practice.

Bloodless liver resection using needle arrays under alternating electromagnetic fields.

BACKGROUND/AIM: Hemostasis is a major difficulty associated with hepatectomies. The authors designed a new thermal surgery system to reduce blood loss. METHODS: The newly designed system consists of an alternating magnetic field generator and stainless steel needle arrays with thermosensitive bands. Lanyu pigs were used: 4 for the Kelly crushing method and 4 for the newly designed method. The procedures used were S4-S5 segmentectomies or left lateral segmentectomies, after which the amount of blood loss and operation times were compared. The pigs were observed for 4 weeks, after which liver pathologies were studied. RESULTS: The blood loss in the method proposed by the authors was almost 0 mL, whereas with the Kelly crushing method it was 116 +/- 35 mL. The method proposed in this study can save 15 to 25 minutes of operation time. The resected liver margins exhibited prominent apoptosis and fibrotic change in the remnant livers. CONCLUSIONS: The method proposed is a novel new way of performing thermal surgery.