Is OLP potentially malignant? A clue from ZNF582 methylation.

OBJECTIVE: Whether oral lichen planus (OLP) was potentially malignant remains controversial. Here, we examined associations of ZNF582 methylation (ZNF582m ) with OLP lesions, dysplastic features and squamous cell carcinoma (OSCC). MATERIALS AND METHODS: This is a case-control study. ZNF582m was evaluated in both lesion and adjacent normal sites of 42 dysplasia, 90 OSCC and 43 OLP patients, whereas ZNF582m was evaluated only in one mucosal site of 45 normal controls. High-risk habits affecting ZNF582m such as betel nut chewing and cigarette smoking were also compared in those groups. RESULTS: OLP lesions showed significantly lower ZNF582m than those of dysplasia and OSCC. At adjacent normal mucosa, ZNF582m increased from patients of OLP, dysplasia, to OSCC. In addition, ZNF582m at adjacent normal sites in OLP patients was comparable to normal mucosa in control group. Dysplasia/OSCC patients with high-risk habits exhibited significantly higher ZNF582m than those without high-risk habits. However, ZNF582m in OLP patients was not affected by those high-risk habits. CONCLUSIONS: OLP is unlikely to be potentially malignant based on ZNF582m levels. ZNF582m may also be a potential biomarker for distinguishing OLP from true dysplastic features and OSCC, and for monitoring the malignant transformation of OLP, potentially malignant disorders with dysplastic features and OSCC.

Coarse-to-fine interaction on perceived depth in compound grating.

To encode binocular disparity, the visual system uses a pair of left eye and right eye bandpass filters with either a position or a phase offset between them. Such pairs are considered to exit at multiple scales to encode a wide range of disparity. However, local disparity measurements by bandpass mechanisms can be ambiguous, particularly when the actual disparity is larger than a half-cycle of the preferred spatial frequency of the filter, which often occurs in fine scales. In this study, we investigated whether the visual system uses a coarse-to-fine interaction to resolve this ambiguity at finer scales for depth estimation from disparity. The stimuli were stereo grating patches composed of a target and comparison patterns. The target patterns contained spatial frequencies of 1 and 4 cycles per degree (cpd). The phase disparity of the low-frequency component was 0° (at the horopter), -90° (uncrossed), or 90° (crossed), and that of the high-frequency components was changed independent of the low-frequency disparity, in the range between -90° (uncrossed) and 90° (crossed). The observers' task was to indicate whether the target appeared closer to the comparison pattern, which always shared the disparity with the low-frequency component of the target. Regardless of whether the comparison pattern was a 1-cpd + 4-cpd compound or a 1-cpd simple grating, the perceived depth order of the target and the comparison varied in accordance with the phase disparity of the high-frequency component of the target. This effect occurred not only when the low-frequency component was at the horopter, but also when it contained a large disparity corresponding to one cycle of the high-frequency component (±90°). Our findings suggest a coarse-to-fine interaction in multiscale disparity processing, in which the depth interpretation of the high-frequency changes based on the disparity of the low-frequency component.

A Hardware-Friendlyand High-Efficiency H.265/HEVC Encoder for Visual Sensor Networks.

Visual sensor networks (VSNs) have numerous applications in fields such as wildlife observation, object recognition, and smart homes. However, visual sensors generate vastly more data than scalar sensors. Storing and transmitting these data is challenging. High-efficiency video coding (HEVC/H.265) is a widely used video compression standard. Compare to H.264/AVC, HEVC reduces approximately 50% of the bit rate at the same video quality, which can compress the visual data with a high compression ratio but results in high computational complexity. In this study, we propose a hardware-friendly and high-efficiency H.265/HEVC accelerating algorithm to overcome this complexity for visual sensor networks. The proposed method leverages texture direction and complexity to skip redundant processing in CU partition and accelerate intra prediction for intra-frame encoding. Experimental results revealed that the proposed method could reduce encoding time by 45.33% and increase the Bjontegaard delta bit rate (BDBR) by only 1.07% as compared to HM16.22 under all-intra configuration. Moreover, the proposed method reduced the encoding time for six visual sensor video sequences by 53.72%. These results confirm that the proposed method achieves high efficiency and a favorable balance between the BDBR and encoding time reduction.

Pre-operative MRI features predict early post-operative recurrence of hepatocellular carcinoma with different degrees of pathological differentiation.

PURPOSE: To investigate the value of pre-operative gadoxetate disodium (Gd-EOB-DTPA) enhanced MRI predicting early post-operative recurrence (< 2 years) of hepatocellular carcinoma (HCC) with different degrees of pathological differentiation. METHODS: Retrospective analysis of pre-operative MR imaging features of 177 patients diagnosed as suffering from HCC and that underwent radical resection. Multivariate logistic regression assessment was adopted to assess predictors for HCC recurrence with different degrees of pathological differentiation. The area under the curve (AUC) of receiver operating characteristics (ROC) was utilized to assess the diagnostic efficacy of the predictors. RESULTS: Among the 177 patients, 155 (87.5%) were males, 22 (12.5%) were females; the mean age was 49.97 ± 10.71 years. Among the predictors of early post-operative recurrence of highly-differentiated HCC were an unsmooth tumor margin and an incomplete/without tumor capsule (p = 0.037 and 0.033, respectively) whereas those of early post-operative recurrence of moderately-differentiated HCC were incomplete/without tumor capsule, peritumoral enhancement along with peritumoral hypointensity (p = 0.006, 0.046 and 0.004, respectively). The predictors of early post-operative recurrence of poorly-differentiated HCC were peritumoral enhancement, peritumoral hypointensity, and tumor thrombosis (p = 0.033, 0.006 and 0.021, respectively). The AUCs of the multi-predictor diagnosis of early post-operative recurrence of highly-, moderately-, and poorly-differentiated HCC were 0.841, 0.873, and 0.875, respectively. The AUCs of the multi-predictor diagnosis were each higher than for those predicted separately. CONCLUSIONS: The imaging parameters for predicting early post-operative recurrence of HCC with different degrees of pathological differentiation were different and combining these predictors can improve the diagnostic efficacy of early post-operative HCC recurrence.

Butylidenephthalide Abrogates the Snail-Induced Cancer Stemness in Oral Carcinomas.

Oral cancer is one of the most common cancers worldwide, especially in South Central Asia. It has been suggested that cancer stem cells (CSC) play crucial roles in tumor relapse and metastasis, and approaches to target CSC may lead to promising results. Here, aldehyde dehydrogenase 1 (ALDH1) and CD44 were utilized to isolate CSCs of oral cancer. Butylidenephthalide, a bioactive phthalide compound from Angelica sinensis, was tested for its anti-CSC effects. MTT assay showed that a lower concentration of butylidenephthalide was sufficient to inhibit the proliferation of patient-derived ALDH1+/CD44+ cells without affecting normal cells. Administration of butylidenephthalide not only reduced ALDH1 activity and CD44 expression, it also suppressed the migration, invasion, and colony formation abilities of ALDH1+/CD44+ cells using a transwell system and clonogenic assay. A patient-derived xenograft mouse model supported our in vitro findings that butylidenephthalide possessed the capacity to retard tumor development. We found that butylidenephthalide dose-dependently downregulated the gene and protein expression of Sox2 and Snail. Our results demonstrated that overexpression of Snail in ALDH1-/CD44- (non-CSCs) cells induced the CSC phenotypes, whereas butylidenephthalide treatment successfully diminished the enhanced self-renewal and propagating properties. In summary, this study showed that butylidenephthalide may serve as an adjunctive for oral cancer therapy.

Oral microbial dysbiosis and its performance in predicting oral cancer.

Dysbiosis of oral microbiome may dictate the progression of oral squamous cell carcinoma (OSCC). Yet, the composition of oral microbiome fluctuates by saliva and distinct sites of oral cavity and is affected by risky behaviors (smoking, drinking and betel quid chewing) and individuals' oral health condition. To characterize the disturbances in the oral microbial population mainly due to oral tumorigenicity, we profiled the bacteria within the surface of OSCC lesion and its contralateral normal tissue from discovery (n = 74) and validation (n = 42) cohorts of male patients with cancers of the buccal mucosa. Significant alterations in the bacterial diversity and relative abundance of specific oral microbiota (most profoundly, an enrichment for genus Fusobacterium and the loss of genus Streptococcus in the tumor sites) were identified. Functional prediction of oral microbiome shown that microbial genes related to the metabolism of terpenoids and polyketides were differentially enriched between the control and tumor groups, indicating a functional role of oral microbiome in formulating a tumor microenvironment via attenuated biosynthesis of secondary metabolites with anti-cancer effects. Furthermore, the vast majority of microbial signatures detected in the discovery cohort was generalized well to the independent validation cohort, and the clinical validity of these OSCC-associated microbes was observed and successfully replicated. Overall, our analyses reveal signatures (a profusion of Fusobacterium nucleatum CTI-2 and a decrease in Streptococcus pneumoniae) and functions (decreased production of tumor-suppressive metabolites) of oral microbiota related to oral cancer.

LncRNA MEG3 inhibits self-renewal and invasion abilities of oral cancer stem cells by sponging miR-421.

BACKGROUND/PURPOSE: Oral cancer stem cells (CSCs) have been considered as the key cells that are implicated in tumor recurrence and metastasis. In recent years, great attention has been paid to the significance of various non-coding RNAs due to their regulatory roles in oral CSCs. Although the function of long non-coding RNA MEG3 in various cancers has been investigated, its effects on the features of oral CSCs remained to be determined. METHODS: The expression levels of MEG3 in tongue squamous cell carcinomas and prognostic effect have been evaluated. We assessed the expression of MEG3 in sphere cells (oral CSCs) using qRT-PCR. Secondary sphere formation and invasion assays were conducted to evaluate the self-renewal and metastatic abilities, respectively. Bioinformatics software and luciferase reporter assay were used to predict and verify the relationship between MEG3 and miR-421. RESULTS: MEG3 was downregulated in the tissues of oral cancer and associated with a poor prognosis. In oral CSCs, the expression of MEG3 was repressed and overexpression of MEG3 resulted in suppression of self-renewal and invasion abilities. Luciferase reporter assay showed that miR-421 directly interacted with MEG3, and our subsequent experiment demonstrated that elevation of miR-421 reversed the MEG3-inhibited characteristics of oral CSCs. CONCLUSION: Our findings suggest that MEG3 can serve as a tumor suppressor in oral CSCs by impeding the action of miR-421. Moreover, targeting MEG3-miR-421 axis has the potential to mitigate the tumor recurrence and metastasis.

Honokiol inhibits arecoline-induced oral fibrogenesis through transforming growth factor-ß/Smad2/3 signaling inhibition.

BACKGROUND/PURPOSE: The habit of areca nut chewing has been regarded as an etiological factor of precancerous oral submucous fibrosis (OSF). In the present study, we aimed to evaluate the anti-fibrosis effect of honokiol, a polyphenolic component derived from Magnolia officinalis. METHODS: The cytotoxicity of honokiol was tested using normal and fibrotic buccal mucosal fibroblasts (fBMFs) derived from OSF tissues. Collagen gel contraction, Transwell migration, invasion, and wound healing capacities were examined. Besides, the expression of TGF-ß/Smad2 signaling as well as α-SMA and type I collagen were measured as well. RESULTS: Honokiol exerted higher cytotoxicity of fBMFs compared to normal cells. The arecoline-induced myofibroblast activities, including collagen gel contractility, cell motility and wound healing capacities were all suppressed by honokiol treatment. In addition, the expression of the TGF-ß/Smad2 pathway was downregulated along with a lower expression of α-SMA and type I collagen in honokiol-receiving cells. CONCLUSION: Our data suggest that honokiol may be a promising compound to alleviate the progression of oral fibrogenesis and prevent the transformation of OSF oral epithelium into cancer.

Antimetastatic Effects of Sesamin on Human Head and Neck Squamous Cell Carcinoma through Regulation of Matrix Metalloproteinase-2.

BACKGROUND: Sesamin is a lignin present in sesame oil from the bark of Zanthoxylum spp. Sesamin reportedly has anticarcinogenic potential and exerts anti-inflammatory effects on several tumors. Hypothesis/Purpose: However, the effect of sesamin on metastatic progression in human head and neck squamous carcinoma (HNSCC) remains unknown in vitro and in vivo; hence, we investigated the effect of sesamin on HNSCC cells in vitro. METHODS AND RESULTS: Sesamin-treated human oral cancer cell lines FaDu, HSC-3, and Ca9-22 were subjected to a wound-healing assay. Furthermore, Western blotting was performed to assess the effect of sesamin on the expression levels of matrix metalloproteinase (MMP)-2 and proteins of the MAPK signaling pathway, including p-ERK1/2, P-p38, and p-JNK1/2. In addition, we investigated the association between MMP-2 expression and the MAPK pathway in sesamin-treated oral cancer cells. Sesamin inhibited cell migration and invasion in FaDu, Ca9-22, and HSC-3 cells and suppressed MMP-2 at noncytotoxic concentrations (0 to 40 µM). Furthermore, sesamin significantly reduced p38 MAPK and JNK phosphorylation in a dose-dependent manner in FaDu and HSC-3 cells. CONCLUSIONS: These results indicate that sesamin suppresses the migration and invasion of HNSCC cells by regulating MMP-2 and is thus a potential antimetastatic agent for treating HNSCC.

Effects of Chinese Medicinal Formula BNG-1 on Phosphodiesterase 3B Expression, Hepatic Steatosis, and Insulin Resistance in High Fat Diet-induced NAFLD Mice.

Background: Chinese medicinal formula BNG-1, a non-specific inhibitor of phospho-diesterases (PDEs), can be considered as a potential anti-inflammatory agent. The present study was aimed at determining the effects of BNG-1 on the development of non-alcoholic fatty liver disease (NAFLD) in mice. Design and Methods: Male CD1 mice were randomly divided into seven groups, the control Con (4) and Con (8)+saline groups were fed a standard control diet for four or eight weeks; the experimental HFD (4) and HFD (8)+saline groups were fed a high fat diet for four or eight weeks; the HFD (8)+LBNG, HFD (8)+MBNG, and HFD (8)+HBNG groups received a high fat diet along with low, moderate or high doses of BNG-1 (0.026, 0.035, and 0.052g/30g body weight) which was administered for the last four weeks of an eight-week experimental period. After the end of experiment, blood and tissue samples were taken and analyzed. Results: Mice in the HFD (4) group had higher levels of alanine aminotransferase (ALT), plasma and hepatic triglyceride and cholesterol, and homeostasis model assessment-estimated insulin resistance (HOMA-IR) compared with mice in the Con (4) group. Mice receiving the high fat diet along with the BNG-1 supplement had decreased body weight gains and lower visceral fat weights compared with the HFD (8)+saline group. They had also significantly reduced levels of abnormal ALT and HOMA-IR, and improved blood lipid profile. BNG-1-treated mice exhibited reduced hepatic lipid accumulation, lower oxidative stress, and decreased expression of pro-inflammatory cytokines (TNF-α and IL-1ß). Furthermore, BNG-1 treatment resulted in down-regulation of hepatic cyclic-AMP dependent PDE3B and up-regulation of PDE3B expression in epididymis adipose tissue. Conclusions: BNG-1 mediated changes in PDE3B expression along with reduction in oxidative stress and inflammation. BNG-1 may ameliorate insulin resistance and hepatic steatosis in the NAFLD mouse model.

miR-200c inhibits the arecoline-associated myofibroblastic transdifferentiation in buccal mucosal fibroblasts.

BACKGROUND/PURPOSE: MicroRNA-200c (miR-200c) recently emerged as an important regulator of tumorigenesis and cancer metastasis, however, its role in regulating oral submucous fibrosis (OSF) remains unknown. In this study, we investigated the functional role of miR-200c in myofibroblastic differentiation activity and identified its potential target. METHODS: qRT-PCR was applied to assess the expression of miR-200c in OSF tissues and fibrotic buccal mucosal fibroblasts (fBMFs). Arecoline, a major areca nut alkaloid, was utilized to explore whether the expression of miR-200c would alter following stimulation. Collagen gel contraction, migration and invasion capabilities were examined in arecoline-stimulated BMFs as wells as in fBMFs. Luciferase reporter assay was conducted to show the relationship between miR-200c and ZEB1. RESULTS: Our results showed that the expression of miR-200c was downregulated in OSF specimen and fBMFs. Arecoline treatment dose-dependently reduced the relative expression of miR-200c in normal BMFs. Overexpression of miR-200c impeded the arecoline-induced collagen gel contraction, migration, invasion and wound healing capacities. Moreover, ectopic expression of miR-200c in fBMFs successfully reduced the increased collagen gel contractility and invasion abilities. Our results demonstrated that ZEB1 was a direct target of miR-200c, and overexpression of miR-200c inhibited the expression of ZEB1 and α-SMA. CONCLUSION: These findings suggest that downregulation of miR-200c in OSF may be involved in the pathogenesis of areca nut-associated OSF through regulation of ZEB1.

miR-145 mediates the anti-cancer stemness effect of photodynamic therapy with 5-aminolevulinic acid (ALA) in oral cancer cells.

5-Aminolevulinic acid-mediated photodynamic therapy (ALA-PDT) has been used in the treatment of various precancerous and malignant lesions. Our previous work has demonstrated that ALA-PDT possesses the potential to serve as an adjuvant therapy against head and neck cancer via eliminating the cancer stem cells (CSCs) property. This study aimed to further investigate the possible molecular mechanism underlying the effect of ALA-PDT. Our results revealed that ALA-PDT upregulated the expression of microRNA-145 (miR-145) in two oral cancer cell lines. Overexpression of miR-145 in oral CSCs further enhanced the treatment effect of ALA-PDT with lower self-renewal, invasion capacities and reduced CD44 expression, while inhibition of miR-145 exhibited the opposite phenomena. These findings suggest that the anti-CSCs effect of ALA-PDT is due to an elevation of miR-145.

The perceived depth from disparity as function of luminance contrast.

Does human vision show the contrast invariance expected of an ideal stereoscopic system for computing depth from disparity? We used random-dot stereograms to investigate the luminance contrast effect on perceived depth from disparity. The perceived depth of disparity corrugations was measured by adjusting the length of a horizontal line to match the perceived depth of the corrugations at various luminance contrasts. At each contrast, the perceived depth increased with disparity up to a critical value, decreasing with further increases in disparity. Both the maximum perceived depth and the disparity modulation level where this maximum occurred changed as a sigmoid function of luminance contrast. These results show that perceived depth from disparity depends in a complex manner on the luminance contrast in the image, providing significant limitations on depth perception at low contrasts in a lawful manner but that are incompatible with existing models of cortical disparity processing.

Volume changes in remnant thyroid tissue after thyroidectomy in Graves disease.

BACKGROUND/PURPOSE: Surgery is one of the treatment choices for Graves disease. The residual thyroid tissue may shrink or become larger. The object of this study was trying to find out what factors affect the residual thyroid gland volume change after thyroidectomy in Graves disease. METHODS: We followed thyroid volume changes by ultrasonography in 101 patients with Graves disease who underwent one side lobectomy and another side subtotal thyroidectomy from 1996 to 2006. These patients were divided into three groups according to the residual thyroid size increasing, no change in size, and shrinking. We checked the factors as follows: age, body weight, thyroid-stimulating hormone (TSH) level, TSH-receptor antibody level, anti-thyroid peroxidase (TPO) antibody level, total thyroid volume before and after thyroidectomy, and degree of lymphocyte infiltration. RESULTS: We found that young age and lower residual volume ratio were the most powerful two factors affecting remnant thyroid gland volume changing. We also found that there is no significant correlation between TSH levels and thyroid volume change, nor TSH-receptor antibody titer or thyroid volume change. CONCLUSION: Age and residual volume ratio were the most powerful two factors in this study.

Use of reconstruction plates prebent on three-dimensional models to reduce the complications of mandibular reconstruction.

Background/purpose: Though the gold standard method for mandible reconstruction of the defect from segmental mandibulectomy is by osseous flap or graft, using reconstruction plates is still indicated in some cases. Traditionally, the plate is bended immediately after the segmental mandibulectomy by freehand. However, it's difficult to fit well to the original position of mandible, which may result in more complications. This study therefore aimed to investigate whether using prebent plates on computer-aided 3D printing models could reduce the complication rate. Materials and methods: Patients who received mandible reconstruction by reconstruction plate from 2018 to 2022 were enrolled and evaluated in this study. The data, including demographics, indications for surgery, pre-existed preoperative and postoperative therapies, classification of defects, and postoperative outcomes were collected and analyzed. Results: A total of 52 patients were enrolled in our study. The prebent group exhibited a significantly lower complication rate than that of the immediately bent group (P = 0.012). Other risk factors of plate complications included postoperative adjuvant radiotherapy (P = 0.017) and previous surgery (P = 0.047). The complication-free survival rate was also better in the prebent group in a 3-year follow-up period (P = 0.012). Conclusion: Prebent plates on computer-aided printing models proved to be an effective approach to reduce the complications for mandibular reconstruction in segmental mandibulectomy.

Improving the Diagnostic Performance by Adding Methylation Marker to Conventional Visual Examination in Identifying Oral Cancer.

BACKGROUND: Visual oral examination (VOE) is a conventional oral cancer screening method. This study aimed to evaluate the value of methylation marker to assist VOE in identifying oral epithelial dysplasia and oral squamous cell carcinoma (OED/OSCC) from non-cancerous lesions in a real-world situation. METHODS: 201 patients with high-risk personal habits who self-perceived oral anomaly were VOE examined, ZNF582 methylation (ZNF582m) tested, and histologically diagnosed. RESULTS: Among them, 132 patients (65.7%) were histologically diagnosed OED/OSCC. Using VOE, 56.1% OED/OSCC patients had possible oral cancer, whereas 37.7% non-OED/OSCC patients had leukoplakia. ZNF582m-positive was detected in 90.2% OED/OSCC patients and 44.9% non-OED/OSCC patients. Various logistic regression models were postulated to evaluate the diagnostic performance of conventional VOE and new strategies using ZNF582m. ROC analysis and its corresponding C-index demonstrated that either triage or co-testing models of VOE and ZNF582m could improve diagnostic performance and discriminative abilities compared with the VOE only approach. CONCLUSIONS: In conclusion, methylation marker test shows equivalent performance to an experienced judgment by oral maxillofacial surgeons and plays a significantly supplementary role in increasing the efficacy in identifying oral malignant lesions. ZNF582m may be an especially important tool for family physicians or general dentists to properly diagnose suspicious oral lesions.

A gain-control disparity energy model for perceived depth from disparity.

Luminance contrast is one of the key factors in the visibility of objects in the world around us. Previous work has shown that the perceived depth from binocular disparity depends profoundly on the luminance contrast of the image. This dependence cannot be explained by existing disparity models, such as the well-established disparity energy model, because they predict no effect of luminance contrast on depth perception. Here, we develop a model for disparity processing that incorporates contrast normalization of the neural response into the disparity energy model to account for the contrast dependence of perceived depth from disparity. Our model contains an array of disparity channels, each with a different disparity selectivity. The binocular images are first processed by the left- and right-eye receptive fields of each channel. The outputs of the two receptive fields are combined linearly as the excitatory disparity sensitivity and then fed into a nonlinear contrast gain control mechanism. The perceived depth is determined by the weighted average of all the disparity channels that respond to the binocular images. This model provides the first analytic account of how luminance contrast affects perceived depth from disparity.

Suppressive effects of extracts from the aerial part of Coriandrum sativum L. on LPS-induced inflammatory responses in murine RAW 264.7 macrophages.

BACKGROUND: Coriandrum sativum is used not only as a spice to aid flavour and taste values in food, but also as a folk medicine in many countries. Since little is known about the anti-inflammatory ability of the aerial parts (stem and leaf) of C. sativum, the present study investigated the effect of aerial parts of C. sativum on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. We further explored the molecular mechanism underlying these pharmacological properties of C. sativum. RESULTS: Ethanolic extracts from both stem and leaf of C. sativum (CSEE) significantly decreased LPS-induced nitric oxide and prostaglandin E(2) production as well as inducible nitric oxide synthase, cyclooxygenase-2, and pro-interleukin-1beta expression. Moreover, LPS-induced IkappaB-alpha phosphorylation and nuclear p65 protein expression as well as nuclear factor-kappaB (NF-kappaB) nuclear protein-DNA binding affinity and reporter gene activity were dramatically inhibited by aerial parts of CSEE. Exogenous addition of CSEE stem and leaf significantly reduced LPS-induced expression of phosphorylated mitogen-activated protein kinases (MAPKs). CONCLUSION: Our data demonstrated that aerial parts of CSEE have a strong anti-inflammatory property which inhibits pro-inflammatory mediator expression by suppressing NF-kappaB activation and MAPK signal transduction pathway in LPS-induced macrophages.

Seeing Global Motion in a Random Dot Image Sequence.

In a stimulus with multiple moving elements, an observer may perceive that the whole stimulus moves in unison if (a) one can associate an element in one frame with one in the next (correspondence) and (b) a sufficient proportion of correspondences signal a similar motion direction (coherence). We tested the necessity of these two conditions by asking the participants to rate the perceived intensity of linear, concentric, and radial motions for three types of stimuli: (a) random walk motion, in which the direction of each dot was randomly determined for each frame, (b) random image sequence, which was a set of uncorrelated random dot images presented in sequence, and (c) global motion, in which 35% of dots moved coherently. The participants perceived global motion not only in the global motion conditions but also in the random image sequences, though not in random walk motion. The type of perceived motion in the random image sequences depends on the spatial context of the stimuli. Thus, although there is neither a fixed correspondence across different frames nor a coherent motion direction, observers can still perceive global motion in the random image sequence. This result cannot be explained by motion energy or local aperture border effects.