miR-135b reverses chemoresistance of non-small cell lung cancer cells by downregulation of FZD1

BackgroundNon-small cell lung cancer (NSCLC) chemoresistance usually limits the clinical efficacy of chemotherapeutic approaches. However, few reports have revealed the regulation of miR-135b and Frizzled-1 (FZD1) involved in NSCLC chemoresistance.MethodsTo identify the mechanism of miR-135b and FZD1 in NSCLC chemoresistance and to observe their biological functions, we detected the expression levels of miR-135b and FZD1 by conducting quantitative real-time polymerase chain reaction (RT-qPCR) and modified the expressions of miR-135b and FZD1 by transiently transfecting cells with miR-135b mimics or FZD1-siRNA. The 3′-untranslated region (3′-UTR) of FZD1 combined with miR-135b was verified through dual-luciferase reporter assay.ResultsCompared with that in A549 parental cell lines, the miR-135b expression in drug-resistant lung cancer cell lines (A549/DDP) was decreased and their FZD1 expression was increased. The increased miR-135b expression and silenced FZD1 expression enhanced the sensitivity of resistant cells to cisplatin treatment. The high expression of miR-135b in A549/DDP cells remarkably decreased the mRNA levels of FZD1. FZD1 was further identified as the functional downstream target of miR-135b by directly targeting the 3′-UTR of FZD1.ConclusionThe amplification of miR-135b suppressed NSCLC chemoresistance by directly mediating the FZD1 downregulation.     

New mechanisms of disease and parasite-host interactions

An unconventional interaction between a patient and parasites was recently reported, in which parasitic cells invaded host’s tissues, establishing several tumors. This finding raises various intriguing hypotheses on unpredicted forms of interplay between a patient and infecting parasites.Here we present four unusual hypothetical host-parasite scenarios with intriguing medical consequences. Relatively simple experimental designs are described in order to evaluate such hypotheses.The first one refers to the possibility of metabolic disorders in parasites intoxicating the host. The second one is on possibility of patients with inborn errors of metabolism (IEM) being more resistant to parasites (due to accumulation of toxic compounds in the bloodstream). The third one refers to a mirrored scenario: development of tumors in parasites due to ingestion of host’s circulating cancer cells. The last one describes a complex relationship between parasites accumulating a metabolite and supplying it to a patient with an IEM.     

Non-invasive Assessment of Changes in Muscle Injury by Ultrasound Shear Wave Elastography: An Experimental Study in Contusion Model

The present study investigated the potential of ultrasound shear wave elastography (SWE) in assessment of muscle stiffness in muscle injury. SWE was performed on the injured muscle in 30 New Zealand rabbits that were randomly assigned to three groups: the contusion group, which was not treated with an efficient therapeutic strategy after muscle injury; the treatment group, which was treated with a therapeutic scheme after muscle injury; and the healthy group, which was not injured and served as a control. Both the mean Young's modulus (E_mean) and the maximum Young's modulus (E_max) were obtained pre-injury and 0.5, 1, 3, 5, 7, 14 and 28 d post-injury. At these time points, a rabbit in each group was randomly selected for biopsy for histopathological observation as well as comparison with Young's modulus. Eventually, all muscle tissues were collected for histologic analysis of collagen fiber formation. The contusion group had the highest Young's modulus, followed by the treatment group and then the healthy group (p < 0.05). In both the contusion and treatment groups, E_mean and E_max gradually increased within 1–3 d after injury, followed by a gradual decrease. Compared with the healthy group, histopathologic analysis of the contusion and treatment groups revealed the myofibril destruction process, inflammatory reaction and myofibril regeneration. The amount of collagen fibers in the contusion group was maximal compared with the treated and healthy groups (p?=?0.001 and p < 0.001, respectively). There were more collagen fibers in the treatment group than in the healthy group (p?=?0.003). The abundance of collagen fibers was positively correlated with the value of Young's modulus (E_mean: r?=?0.706, p < 0.001; E_max: r?=?0.761, p < 0.001). Thus, SWE can be used to detect pathologic changes in injured muscle and to monitor therapeutic effects.     

改良后腹腔镜手术方式在上尿路肿瘤治疗的可行性和安全性*

目的探讨改良后腹腔镜手术方式在上尿路肿瘤治疗的可行性及安全性。方法回顾性分析该院40例腹腔镜手术治疗肾盂癌及中上段上尿路肿瘤患者病例,其中21例患者选择改良后腹腔镜联合经尿道电切镜下肾、输尿管切除术(A组),另外19例患者采用后腹腔镜联合下腹部小切口、经尿道电切镜肾、输尿管切除术(B组)。比较两种手术方式的手术时间、术中出血量、术后留置引流管时间、术后首次肛门排气时间及术后住院时间的差异。结果两组共40名患者,手术均顺利完成,无中转手术。A组与B组患者平均年龄、性别比、肿瘤位置比较,差异无统计学意义(P0.05)。A组手术时间较B组明显缩短(P0.01);A组患者术后住院时间明显少于B组(P0.05)。两组均无术中、术后并发症。A、B组间术中失血量、术后留置引流管时间、术后首次肛门排气时间均差异无统计学意义(P0.05)。结论和后腹腔镜联合下腹部小切口手术方式相比,改良后腹腔镜手术方式安全有效,可缩短手术时间,减少患者术后住院时间,可在上尿路肿瘤,特别是肾盂及中上段输尿管肿瘤的治疗中选择应用。