[Analysis on the ultrasonic characteristics of tonsillar lymphoma].

Objective: To analyze the ultrasonic features of tonsillar lymphoma to improve the diagnostic accuracy. Methods: The clinical, pathological and ultrasonic data of nine patients with tonsillar lymphoma confirmed by pathology at Tianjin Medical University Cancer Institute and Hospital during June 2015 and June 2022 were analyzed retrospectively, and the characteristics of their ultrasonic images were summarized. Results: All 9 cases of tonsil lymphoma were unilateral tonsil disease, including 4 cases on the left side and 5 cases on the right side. The average maximum diameter of tonsil lymphoma in 9 cases was 4.32 cm. There were 3 cases with simultaneous involvement of tonsil and cervical lymph nodes, all of which were ipsilateral lymph nodes. Gray scale ultrasound showed that the lesions were hypoechoic, with clear boundaries in 7 cases and unclear boundaries in 2 cases. The shape was full and irregular in 5 cases and oval in 4 cases. The echo was uniform in 7 cases and uneven in 2 cases. Color Doppler ultrasonography showed abundant internal blood flow signal in 1 case, a little dotted linear internal blood flow signal in 5 cases, and no obvious internal blood flow signal in 3 cases. Conclusions: The ultrasonic features of tonsillar lymphoma include hypoechoic area, clear boundary, full shape, irregular and uniform internal echo, no or low linear signal of internal blood flow. Ultrasonography is of great value in the diagnosis of this disease and can help clinical decision-making.

Saikosaponin A mitigates the progression of Parkinson's disease via attenuating microglial neuroinflammation through TLR4/MyD88/NF-κB pathway.

OBJECTIVE: Neuroinflammation caused by excessive microglial cell activation and the subsequent death of dopaminergic neurons plays a role in the pathogenesis of Parkinson's disease (PD). Saikosaponin A (Ssa), a triterpene saponin derived from Radix Bupleuri, has anti-inflammatory and antioxidant functions. This research aimed to investigate whether Ssa has a therapeutic effect on PD. MATERIALS AND METHODS: BV2 microglia- and SH-SY5Y cells were treated with a neurotoxin N-methyl-4- phenylpyridinium (MPP+) and Ssa. Cell viability, apoptosis, inflammatory reactions, and expression levels of oxidative stress mediators were assessed. A PD rat model was created by intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), followed by the Ssa treatment. Hematoxylin-eosin (H&E) staining, Nissl staining, and immunohistochemistry were used to detect neuronal apoptosis and microglial activation. Open-field test (OFT) was performed to evaluate the locomotion of the rats. The underlying mechanism of Ssa effect in PD was explored using network pharmacology analysis and verified experimentally. RESULTS: Ssa dampened neuronal apoptosis and had anti-inflammatory and anti-oxidative stress proprieties in MPP+-treated SH-SY5Y cells and BV2 microglia. As shown in in-vivo experiments, Ssa reduced MPTP-mediated neuronal apoptosis and motor dysfunction and lowered the expression of inflammatory factors and oxidative stressors in the substantia nigra (SN) of the PD rat. Additionally, Ssa inactivated the TLR4/MyD88/NF-κB pathway. CONCLUSIONS: This study provides the first evidence that Ssa prevents dopaminergic neurodegeneration caused by microglia activation by modulating the TLR4/MyD88/NF-κB axis.

[Pathological features of early gastric cancer and its background mucosa after eradication of Helicobacter pylori and their implications for biopsy diagnosis].

Objective: To investigate the clinicopathological changes of early gastric cancer, especially its background mucosa, after the eradication of Helicobacter pylori (H. pylori), and to investigate the causes of underdiagnosis in preoperative biopsy pathology. Methods: Ninety cases of early gastric cancer after H. pylori eradication and 120 cases of endoscopic submucosal dissection (ESD) specimens without H. pylori eradication and their corresponding biopsy specimens were collected from Beijing Friendship Hospital Affiliated to Capital Medical University during 2016-2021. The clinicopathological data of the patients were analyzed, and the histopathological characteristics and immunophenotypic results compared. Results: Compared with the early gastric cancer without H. pylori eradication history, the histopathological type of early gastric cancer after H. pylori eradication was differentiated adenocarcinoma, with staggered distribution of cancerous and non-cancerous epithelium in the tumor area. The morphologic characteristics of gastric mucosa in the background of early gastric cancer after H. pylori eradication, were distinctive, including widening of the opening of enterosylated glandular ducts, serrated change of luminal margin, eosinophilic and microvesicular cytoplasm of enterosylated epithelium. Low-grade atypia existed in gastric cancer epithelial cells after sterilization, which might lead to underdiagnosis or missed diagnosis in biopsy pathology. Conclusions: Early gastric cancer and its background mucosa after H. pylori eradication have unique morphological characteristics, which can be used as a clue for pathological diagnosis, improve the accuracy of biopsy pathology and reduce the underdiagnosis.

Standard diffusion-weighted, intravoxel incoherent motion, and dynamic contrast-enhanced MRI of musculoskeletal tumours: correlations with Ki67 proliferation status.

AIM: To determine whether quantitative parameters derived from conventional diffusion-weighted imaging (DWI), intravoxel incoherent motion (IVIM), and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) correlate with the Ki67 proliferation status in musculoskeletal tumours. MATERIALS AND METHODS: Twenty-eight patients with musculoskeletal tumours diagnosed via surgical specimen histological analysis who underwent standard DWI, IVIM, and DCE were reviewed retrospectively. The mean standard DWI (apparent diffusion coefficient [ADC]), IVIM (pure diffusion coefficient [D], pseudo-diffusion coefficient [D∗] and perfusion fraction [ƒ]), and DCE (volume transfer constant [Ktrans], rate constant [Kep], and extravascular extracellular volume fraction [Ve]) parameters were measured and correlated with the Ki67 index. The Ki67 value was categorised as high (>20%) or low (≤20%). RESULTS: The ADC and D values correlated negatively with the Ki67 index (r=-0.711∼-0.699, p<0.001), whereas the Ktrans and Kep values correlated positively with the Ki67 index (r=0.389-0.434, p=0.021, 0.041). The ADC and D values were lower (p<0.001), whereas the Ktrans and Kep values were higher (p=0.011, 0.005) in musculoskeletal tumours with a high Ki67 status than in those in a low status. The ADC and D demonstrated the largest area under the receiver-operating characteristic curve (AUC = 0.953), which is statistically bigger than the AUC of Ktrans and Kep (0.784 and 0.802, respectively). CONCLUSION: ADC, D, Ktrans, and Kep correlate with the Ki67 index. ADC and D are the strongest quantitative parameters for predicting Ki67 status.

Correlation of serum vitamin A, D, and E with recurrent respiratory infection in children.

OBJECTIVE: To investigate the correlation of serum vitamin A, D, and E levels with a recurrent respiratory infection (RRI) in children. PATIENTS AND METHODS: The medical records of 422 children with RRI (a study group) in Cangzhou Central Hospital from January 2015 to December 2018 were retrospectively analyzed (the study group was divided into an active group and a stable group). Further 100 healthy children who underwent physical examination at the same time were enrolled as a control group. High-performance liquid chromatography (HPLC) was used to determine vitamin A, D, and E levels, so as to analyze their differences between the groups. RESULTS: Vitamin A, D, and E in the active and stable groups were significantly lower than those in the control group (p < 0.001); in the active group they were significantly lower than those in the stable group (p < 0.001). According to partial correlation analysis, in children with active RRI, vitamin A was respectively positively correlated with vitamin D (r=0.945, p < 0.001), and vitamin E (r=0.988, p < 0.001). Moreover, vitamin E was positively correlated with vitamin D (r=0.959, p < 0.001). CONCLUSIONS: The deficiency of vitamin A, D, and E is positively correlated with the disease activity of children with RRI. Therefore, the supplement of vitamin A, D, and E through dietary adjustment is beneficial to the rehabilitation of the children.

The olfactory subgenome and specific odor recognition in forest musk deer.

Olfactory receptors (ORs) are encoded by OR genes. The OR genes in forest musk deer (Moschus berezovskii), which rely on olfaction for reproductive and social communication, are poorly understood. In this study, we analyzed the genome sequence of the forest musk deer to obtain its olfactory subgenome and compared it to other species. A total of 1378 OR-related sequences were detected in the forest musk deer genome including 864 functional genes, 366 pseudogenes and 148 partial genes. These OR genes were classified into Class I and Class II and were further classified into 18 families and 244 subfamilies through sequence identity. Comparative analyses of the OR genes' protein sequences in species from different orders (forest musk deer, human, mouse and dog) showed that 12 clusters were specific to forest musk deer. However, when compared to other Artiodactyl species (i.e. cattle, yak and pig) only two clusters were specific to forest musk deer. The odor identification potential of the OR genes in the forest musk deer was focused mainly on floral, woody, lemon, sweet and fatty odors. We also found that OR genes specific to forest musk deer were involved in the identification of spearmint and caraway. Our work is the first genome-wide analysis of OR genes in forest musk deer. These findings will assist with better understanding the relationship between behavior and olfaction in the forest musk deer and the characteristics of the olfactory subgenome in Artiodactyl mammals.

FERMT1 mediates epithelial-mesenchymal transition to promote colon cancer metastasis via modulation of ß-catenin transcriptional activity.

We previously demonstrated that fermitin family member 1 (FERMT1) was significantly overexpressed in colon cancer (CC) and associated with poor metastasis-free survival. This study aimed to investigate the precise role of FERMT1 in CC metastasis and the mechanism by which FERMT1 is involved in the epithelial-mesenchymal transition (EMT). Correlations between FERMT1 and EMT markers (E-cadherin, Slug, N-cadherin and ß-catenin) were examined via immunohistochemistry in a cohort of CC tissues and adjacent normal colon mucosae. A series of in vitro and in vivo assays were performed to elucidate the function of FERMT1 in CC metastasis and underlying mechanisms. The upregulated expression of FERMT1 in CC tissues correlated positively with that of Slug, N-cadherin and ß-catenin, but correlated inversely with E-cadherin expression. Altered FERMT1 expression led to marked changes in the proliferation, migration, invasion and EMT markers of CC cells both in vitro and in vivo. Investigations of underlying mechanisms found that FERMT1 interacted directly with ß-catenin and activated the Wnt/ß-catenin signaling pathway by decreasing the phosphorylation level of ß-catenin, enhancing ß-catenin nuclear translocation and increasing the transcriptional activity of ß-catenin/TCF/LEF. Activation of the Wnt/ß-catenin pathway by CHIR99021 reversed the effect of FERMT1 knockdown, whereas inhibition of the Wnt/ß-catenin pathway by XAV939 impaired the effect of FERMT1 overexpression on EMT and cell motility. In conclusion, findings of this study suggest that FERMT1 activates the ß-catenin transcriptional activity to promote EMT in CC metastasis.

[A retrospective study of 54 cases with chronic otitis media prepared for staging tympanoplasty].

Objective:To analyze the clinical effect of 54 cases with chronic otitis media prepared for staging tympanoplasty and 19 cases finished staging ossicular reconstruction surgery, evaluate the advantages of different surgery technique.Method:Fifty-four cases with chronic otitis media were planned for staging tympanoplasty surgery and had been received the first stage surgery. Silicagel plates were placed in the tympanic cavity in order to prevent adhesions. Among them, 19 cases had received the second stage ossicular reconstruction, including 10 cases with TORPs and 9 cases with PORPs. The average air bone gaps (ABG) were measured at four frequencies: 500, 1 000, 2 000 and 4 000 Hz.Result:Among the 54 cases, 45 cases had swollen mucosa in the tympanic cavity and eustachian tube, 18 cases had tympanic fibrous adhesions, and 12 cases had fixed or sclerotic stapes. The preoperative ABG of the 54 cases were (38.26±7.88)dB. As for the 19 cases finished the second stage surgery, their preoperative ABG in the first stage were (39.21±7.05)dB, the preoperative ABG in the second stage were (38.82±11.43)dB, and the postoperative ABG after the second stage were (21.77±11.92)dB. The hearing function after staging tympanoplasty was significantly improved compared with the preoperative hearing in the first and the second stage operation (P< 0.01). In addition, the second stage surgery of three cases was postponed because of a good postoperative hearing with (10.42±10.63)dB ABG after the first stage surgery. Up to now, none of the 54 cases suffered from facial palsy, infection and other complications after surgery.Conclusion:Staging tympanoplasty is an important technique to improving hearing and reducing the complications, especially for the cases with chronic otitis media unsuitable for one stage reconstruction of ossicular chain.

Biological effects and clinical application of negative pressure wound therapy: a review.

Negative pressure wound therapy (NPWT) has shown great advantages in the management of a wide range of clinical problems such as wound or chronic wound healing; open wounds with exposed bone, nerve, or tendon; and orthopaedic implants and related infection in the orthopaedics field. Even though it has shown positive efficacy in treating infection (wound infection or orthopaedic implant infection), its molecular mechanisms of action remain unclear and require further exploration. Since NPWT is widely used in the clinical setting, a comprehensive understanding of its biological effect will assist in appropriate clinical application. This review summarises the biological effect of NPWT on bacteria and cell growth as well as the possible mechanisms associated with NPWT applied in wound healing. We also highlight novel antibacterial dressings for NPWT. PubMed, and Web of Science database searches were conducted. Several search terms were used including negative pressure wound therapy, bacterial growth, growth factor, wound healing, dressing. All databases were searched from inception to 2015, references that lacked original resarch were eliminated.

Holocord spinal epidural abscess: Case report and literature review.

Holocord spinal epidural abscess (SEA) is a rare condition. To our knowledge, five cases of SEA have been reported so far, and no consensus has been made on the treatment yet. In this article, we report a case of holocord SEA and review literature to further understanding of SEA. The advent of antibiotic treatment and the recognition of surgical debridement have been important in searching for alternatives to recovery, so the patient was treated surgically together with systemic antibiotics. The patient remained neurologically stable and continued to be clinically in good condition without any low back pain after 1 year. Surgical drainage, together with systemic antibiotics, is the main treatment choice for extensive SEAs. Although treatment should be considered that highlights the importance of examining the factors related to the health and condition of the patients and the anatomy and extent of the abscess, early surgical treatment associated with prolonged antibiotic treatment is necessary.

Side-to-side variation in normal femoral morphology: 3D CT analysis of 122 femurs.

BACKGROUND: The contralateral femur is often used as reference for reconstruction in unilateral hip joint pathology. The objective of this study was to quantify the side-to-side variation in proximal femur. We hypothesized that significant side-to-side differences exist between left and right femur with implications for preoperative planning and leg length discrepancy following hip arthroplasty. MATERIALS AND METHODS: CT-based 3D femoral models were reconstructed for 122 paired femurs in 61 young healthy subjects (46.9±6.8 years) with no history of hip pathology. Side-to-side differences of several femoral morphologic parameters, including femoral head diameter, femoral anteversion, horizontal offset and femoral head center location, were compared and correlated with demographic factors using multiple linear regression. RESULTS: Significant side-to-side differences (P<0.01) were found in femoral anteversion (4.3±3.8°; range: 0.2° to 17.3°), horizontal offset (2.5±2.1mm; range: 0.1 to 10.3mm), and femoral head center location (7.1±3.8mm; range: 0.5 to 19.4mm). The difference in femoral anteversion was strongly correlated with the difference in neck diameter (R(2)=0.79), whereas the difference in horizontal femoral offset was highly correlated with the head diameter difference (R(2)=0.72). Femoral head center difference was correlated with the femoral anteversion, horizontal offset and neck-shaft-angle difference (R(2)=0.82). DISCUSSION: Relying on the anatomic landmarks of the contralateral femur during hip arthroplasty may not necessarily result in restoration of native anatomy and leg-length. Knowledge of the baseline side-to-side asymmetry could provide a range of error that would be tolerable following hip reconstruction. LEVEL OF EVIDENCE: Level IV. TYPE OF STUDY: Retrospective observational study.

Delayed healing of lower limb fractures with bisphosphonate therapy.

INTRODUCTION: Bisphosphonate therapy (BT) is used commonly in the management of osteoporosis. A systematic review was conducted investigating delayed union of lower limb, long bone fractures in patients on BT. We specifically assessed whether BT increases the risk of delayed union or non-union in lower limb, long bone fractures. METHODS: A literature search was conducted in the PubMed and Embase™ on 4 November 2014. Articles that investigated lower limb fractures, history of BT and fracture union were included in the review. RESULTS: A total of 9,809 papers were retrieved and 14 were deemed suitable for this review. The mean time to union in patients on BT was 8.5 months. A longer time to union was reported in a study investigating BT users versus controls (6.5 vs 4.8 months respectively). The mean rate of delayed or non-union for BT associated atypical fractures was 20% per fracture. Specifically in one study, delayed union was more common in the cohort with more than three years of BT (67%) than in the group with less than three years of BT (26%). Surgical fixation was associated with improved outcomes compared with non-operative management. CONCLUSIONS: BT has been described to be associated with multiple adverse outcomes related to atypical fractures. Current evidence recommends operative management for this patient group. Further investigation is required to evaluate the exact effects of BT on lower limb fractures, in particular typical femoral fractures.

Comparative outcomes for three-dimensional conformal versus intensity-modulated radiation therapy for esophageal cancer.

Emerging data suggests a benefit for using intensity modulated radiation therapy (IMRT) for the management of esophageal cancer. We retrospectively reviewed patients treated at our institution who received definitive or preoperative chemoradiation with either IMRT or 3D conformal radiation therapy (3DCRT) between October 2000 and January 2012. Kaplan Meier analysis and the Cox proportional hazard model were used to evaluate survival outcomes. We evaluated a total of 232 patients (138 IMRT, 94 3DCRT) who received a median dose of 50.4 Gy (range, 44-64.8) to gross disease. Median follow up for all patients, IMRT patients alone, and 3DCRT patients alone was 18.5 (range, 2.5-124.2), 16.5 (range, 3-59), and 25.9 months (range, 2.5-124.2), respectively. We observed no significant difference based on radiation technique (3DCRT vs. IMRT) with respect to median overall survival (OS) (median 29 vs. 32 months; P = 0.74) or median relapse free survival (median 20 vs. 25 months; P = 0.66). On multivariable analysis (MVA), surgical resection resulted in improved OS (HR 0.444; P < 0.0001). Superior OS was also associated on MVA with stage I/II disease (HR 0.523; P = 0.010) and tumor length ≤5 cm (HR 0.567; P = 0.006). IMRT was also associated on univariate analysis with a significant decrease in acute weight loss (mean 6% + 4.3% vs 9% + 7.4%, P = 0.012) and on MVA with a decrease in objective grade ≥3 toxicity, defined as any hospitalization, feeding tube, or >20% weight loss (OR 0.51; P = 0.050). Our data suggest that while IMRT-based chemoradiation for esophageal cancer does not impact survival there was significantly less toxicity. In the IMRT group there was significant decrease in weight loss and grade ≥3 toxicity compared to 3DCRT.

ERK5 silencing inhibits invasion of human osteosarcoma cell via modulating the Slug/MMP-9 pathway.

OBJECTIVE: ERK5 is over expressed in a many of human cancers and this overexpression has been associated with metastasis and invasion. Furthermore, ERK5 silencing inhibits aggressive phenotypes of cancer cells. However, mechanisms by which ERK5 regulates tumour progression or metastasis have not been elucidated. In this study, using human osteosarcoma cell lines U2OS as a model, we explored the involvement of ERK5 silencing on invasiveness of U2OS cells. MATERIALS AND METHODS: ERK5 siRNA targeting ERK5 was stably transfected into the human osteosarcoma cell lines U2OS. ERK5 knocked-down U2OS cells was then transfected with Slug cDNA or MMP-9 cDNA plasmid to re-express Slug or MMP-9. Cell proliferation was detected by MTT assay. Cell invasion and metastasis was detected by Matrigel invasion and wound healing assay. An orthotopic nude mouse model of U2OS was applied for in vivo lung metastasis experiments. ERK5, Slug, MMP-9 and E-cadherin were analyzed by real-time PCR, and Western blotting. RESULTS: ERK5 silencing by siRNA in U2OS cells decreased Slug and MMP-9 expression. Compared with the vector-transfected cells, ERK5 knocked-down cells showed reduced migration and invasion in vitro, as well as decreased metastatic potential in experimental metastasis. Re-expression of Slug or MMP-9 in ERK5 knocked-down cells restored the invasive phenotypes. We also discovered that Re-expression of Slug in ERK5 knocked-down cells restored the MMP-9 expression, and re-expression of MMP-9 in ERK5 knocked-down cells did not affect Slug and ERK5 expression. CONCLUSIONS: Our data suggest that ERK5 knockdown inhibits aggressive behaviour of human U2OS cells through modulating Slug signaling and MMP-9 expression.

Knockdown of neuropilin-1 suppresses invasion, angiogenesis, and increases the chemosensitivity to doxorubicin in osteosarcoma cells - an in vitro study.

OBJECTIVES: Neuropilin-1 (NRP-1) is a novel co-receptor for vascular endothelial growth factor (VEGF). NRP-1 expression in osteosarcoma tissues was significantly higher, and high NRP-1 expression was more frequently occurred in osteosarcoma tissues with advanced clinical stage, positive distant metastasis and poor response to chemotherapy. We tested a hypothesis that the NRP-1 gene plays a role in the invasiveness, angiogenesis and chemoresistance of human OS. MATERIALS AND METHODS: To determine the role of NRP-1 in OS, NRP-1 was stably transfected into the human OS cell line MG-63 to increase the NPR-1 level, and NRP-1 siRNA was stably transfected into the human OS cell line SaOS-2 to knockdown of NRP-1. The effect of NRP-1 on invasion and angiogenesis was assessed by Matrigel invasion assay and in vitro angiogenesis assay. Chemosensitivity to doxorubicin was assessed by MTT assay in the MG-63 and SaOS-2 cells following NRP-1 overexpression or siRNA-induced downregulation of NRP-1. RESULTS: The NRP-1 transfected MG-63 cells showed a markedly higher level of invasion in Matrigel invasion assay. The capillary-like structure formation of endothelial cells was also increased by coculture with the NRP-1 transfected MG-63 cells. On the contrary, the NRP-1 siRNA transfected SaOS-2 cells showed a markedly lower level of invasion in Matrigel invasion assay. The capillary-like structure formation of endothelial cells was also repressed by coculture with the NRP-1 siRNA transfected SaOS-2 cells. NRP-1 overexpression in MG-63 cells increased survival of cells after exposure to doxorubicin. In contrast, downregulation of NRP-1 expression in SaOS-2 cells markedly increased chemosensitivity after exposure to doxorubicin. CONCLUSIONS: We suggest that NRP-1 could be used as a biomarker for OS progression and a novel therapeutic or chemopreventive target for human OS treatment.

Comparison of 1-day vs 2-day dosing of high-dose melphalan followed by autologous hematopoietic cell transplantation in patients with multiple myeloma.

High-dose melphalan at 200 mg/m(2) can be administered in 1 day or over 2 consecutive days before autologous hematopoietic cell transplantation (HCT) for multiple myeloma (MM). Limited data exist on the comparison of the two dosing schedules. A retrospective study of 278 consecutive MM patients receiving high-dose melphalan from January 2010 to December 2012 was conducted. Objectives were to compare the length of hospitalization, toxicity profile, response rates, PFS and OS. One hundred and eighty five patients received 2-day dosing and 93 received 1-day dosing. The two end points of the 95% confidence interval (CI) for the difference did not exceed the preselected margin, therefore the length of hospitalization was considered equivalent. No significant differences were found for response rates, PFS and OS.  The toxicity profile was similar with the exception of more frequent ⩾grade 3 oral mucositis in the 2-day group (13.5% vs 5.4%; odds ratio 3.07 (95% CI:1.11-8.48); P=0.03). High-dose melphalan, given either in 1 day or over 2 days, produced comparable treatment outcomes except for increased grade 3/4 mucositis in the 2-day regimen. One-day dosing could shorten the hospital stay by 1 day and may allow better resource utilization.

Targeting Bax interaction sites reveals that only homo-oligomerization sites are essential for its activation.

Bax is a proapoptotic Bcl-2 family member that has a central role in the initiation of mitochondria-dependent apoptosis. However, the mechanism of Bax activation during apoptosis remains unsettled. It is believed that the activation of Bax is mediated by either dissociation from prosurvival Bcl-2 family members, or direct association with BH3-only members. Several interaction sites on Bax that mediate its interactions with other Bcl-2 family members, as well as its proapoptotic activity, have been identified in previous studies by other groups. To rigorously investigate the functional role of these interaction sites, we knocked in their respective mutants using HCT116 colon cancer cells, in which apoptosis induced by several stimuli is strictly Bax-dependent. Bax-mediated apoptosis was intact upon knock-in (KI) of K21E and D33A, which were shown to block the interaction of Bax with BH3-only activators. Apoptosis was partially reduced by KI of D68R, which impairs the interaction of Bax with prosurvival members, and S184V, a constitutively mitochondria-targeting mutant. In contrast, apoptosis was largely suppressed by KI of L70A/D71A, which blocks homo-oligomerization of Bax and its binding to prosurvival Bcl-2 family proteins. Collectively, our results suggest that the activation of endogenous Bax in HCT116 cells is dependent on its homo-oligomerization sites, but not those previously shown to interact with BH3-only activators or prosurvival proteins only. We therefore postulate that critical interaction sites yet to be identified, or mechanisms other than protein-protein interactions, need to be pursued to delineate the mechanism of Bax activation during apoptosis.

In silico analysis of molecular mechanisms of legume lectin-induced apoptosis in cancer cells.

OBJECTIVES: The legume lectin family, one of the most extensively studied plant lectin families, has received increasing attention for the remarkable anti-tumor activities of its members for binding specific cancer cell surface glycoconjugates. MicroRNAs, a class of small, non-coding RNAs, control translation and stability of mRNAs at post-transcriptional and translational levels. To date, accumulating evidence has revealed that microRNAs are involved in progression of a number of human diseases, especially cancers. However, the molecular manners of microRNA-modulated apoptosis in legume lectin-treated cancer cells are still under investigation. MATERIALS AND METHODS: We performed in silico analyses to study the interactions between three typical legume lectins (ConA, SFL and SAL) and some specific sugar-containing receptors (for example, EGFR, TNFR1, HSP70 and HSP90). Additionally, we predicted some relevant microRNAs which could significantly regulate these aforementioned targetreceptors and thus inhibiting down-stream cancer-related signaling pathways. RESULTS: The results showed that these three legume lectins could competitively bind sugar-containing receptors such as EGFR, TNFR1, HSP70 and HSP90 in two ways, via anti-apoptotic or survival pathways. On the one hand, the legume lectins could induce cancer cell death through triggering receptor-mediated signaling pathways, which resulted from indirect binding between legume lectins and mannoses resided in receptors. On the other hand, direct binding between legume lectins and receptors could lead to steric hindrance, which would disturb efficient interactions between them, and thus, the legume lectins would induce cancer cell death by triggering receptor-mediated signaling pathways. In addition, we identified several relevant microRNAs that regulated these targeted receptors, thereby ultimately causing cancer cell apoptosis. CONCLUSIONS: These findings provide new perspectives for exploring microRNA-modulated cell death in legume lectin-treated cancer cells, which could be utilized in combination therapy for future cancer drug development.