Identification of FCER1G as a key gene in multiple myeloma based on weighted gene co-expression network analysis

PURPOSE

Although the prognosis of multiple myeloma (MM) has remarkably improved with the emerge of novel agents, it remains incurable and relapses inevitably. The molecular mechanisms of MM have not been well-studied. Herein, this study aimed to identify key genes in MM.

MATERIALS AND METHODS

The GSE39754 dataset was used to screen differentially expressed genes (DEGs) and construct a co-expression network. Hub nodes were identified in the protein and protein interaction (PPI) network. Datasets GSE13591 and GSE2658 were used to validate hub genes. Moreover, function and gene set enrichment analyses were performed to elucidate the molecular pathogenesis of MM.

RESULTS

In this study, 11 genes were found to be hub genes in the co-expression network, among which four genes (CD68, FCER1G, PLAUR and LCP2) were also identified as hub nodes. In the test dataset GSE13591, CD68 and FCER1G were significantly downregulated in MM. Besides, the areas under the curve (AUCs) of CD68 and FCER1G were greater than 0.8 in both the training dataset and the test dataset. Our results also confirmed that FCER1G highly expressed patients had remarkably longer survival times in MM. Function and pathway enrichment analyses suggested that hub genes were associated with epithelial mesenchymal transition, TNF-α signaling via NF-κB and inflammatory response. GSEA in our study indicated that FCER1G participated in NK cell mediated cytotoxicity and the NOD-like receptor signaling pathway.

CONCLUSION

Our study identified FCER1G as a key gene in MM, providing a novel biomarker and potential molecular mechanisms of MM for further studies.

Clinical study on multi-focused laser in the treatment of vulvar lichen sclerosus

Objective

To investigate the clinical effect of Multi-focused (MF) laser in the treatment of vulvar lichen sclerosus (VLS).

Methods

In this single-center, randomized controlled trial, we compared the effect of fractionated MF laser with other treatments on patients with biopsy-proven VLS. Patients with VLS were enrolled in this study and randomly divided into three groups. Patients in the experimental group were treated with a CO2 laser, control group 1 was treated with radiofrequency, and control group 2 was treated topically with glucocorticoids and soaking with Chinese patent medicine. The pruritus degree, skin elasticity, skin color, lesion scope, and total score were compared before treatment, at one month after treatment, and three months after treatment.

Results

One month after treatment, the pruritus degree, skin elasticity, skin color, lesion scope, and total score decreased in the experimental group, and the differences were statistically significant (P < 0.05). In control group 1, the differences in pruritus degree, skin color, and total score were statistically significant (P < 0.05), but the differences in skin elasticity and lesion scope were not statistically significant (P > 0.05). In control group 2, the differences in pruritus degree and total score were statistically significant (P < 0.05), but the differences in skin elasticity, skin color, and lesion scope were not statistically significant (P > 0.05). At one month after the end of treatment, the differences in pruritus degree, skin elasticity, skin color, lesion scope, and total score among the three groups were not statistically significant. At three months after the end of treatment, the differences in the scores of the five indicators were statistically significant.

Conclusion

For the three treatment methods for VLS, topical corticosteroids + traditional Chinese medicine can quickly relieve itching symptoms in patients, but it cannot significantly improve skin elasticity, skin color, and lesion scope, and VLS easily relapses after treatment. Radiofrequency can improve itching symptoms and skin color but has poor effects on the change of skin elasticity and lesion scope. Multi-focused laser treatment can alleviate the degree of pruritus, improve skin color and elasticity, and narrow the lesion scope, and VLS will not relapse within three months after treatment.

OnclncRNA-626 promotes malignancy of gastric cancer via inactivated the p53 pathway through interacting with SRSF1

Gastric cancer (GC) is a serious health problem worldwide. The potential involvement of long noncoding RNAs in GC progression remains largely unexplored. Here, we identified a novel long noncoding RNA referred to as onclncRNA-626 (oncogenic lncRNA RP11-626H12.3), which was highly upregulated in GC tissues. The high expression levels of onclncRNA-626 in GC patients predicted poor prognoses. Functional assays indicated that onclncRNA-626 could promote the proliferation and metastasis of GC cells in vitro and in vivo. In exploring the molecular mechanisms guiding these functions, we found that onclncRNA-626 specifically interacted with serine- and arginine-rich splicing factor 1 (SRSF1) and increased its stability. SRSF1 was upregulated in GC tissues and correlated with onclncRNA-626 expression and patient survival. Furthermore, RNA-seq data revealed that onclncRNA-626 affected multiple signaling pathways, including the p53 signaling pathway. Rescue experiments showed that onclncRNA-626 probably performed its biological function through SRSF1 mediation of the p53 pathway. Together, our findings demonstrate that onclncRNA-626 promotes GC progression by binding SRSF1; further, this lncRNA is a potential prognostic biomarker for GC patients.

Proportion of Uterine Malignant Tumors in Patients with Laparoscopic Myomectomy: A National Multicenter Study in China

Background:

The Food and Drug Administration recently announced that the use of morcellation may cause fibroids or pelvic dissemination and metastasis of uterine sarcoma; therefore, the use of morcellation is limited in the USA. A large sample study is necessary to assess the proportion of uterine malignant tumors found in patients with laparoscopic myomectomy.

Methods:

A national multicenter study was performed in China. From 2002 to 2014, 33,723 cases were retrospectively selected. We calculated the prevalence and recorded the clinical characteristics of the patients with malignancy after morcellation application. A total of 62 cases were finally pathologically confirmed as malignant postoperatively. Additionally, the medical records of the 62 patients were analyzed in details.

Results:

The proportion of postoperative malignancy after morcellation application was 0.18% (62/33,723) for patients who underwent laparoscopic myomectomy. Nearly 62.9% (39/62) of patients had demonstrated blood flow signals in the uterine fibroids before surgery. And, 23 (37.1%) patients showed rapid growth at the final preoperative ultrasound. With respect to the pathological types, 38 (61.3%) patients had detectable endometrial stromal sarcoma, 13 (21.0%) had detectable uterine leiomyosarcoma, only 3 (3.2%) had detectable carcinosarcoma, and 5 (8.1%) patients with leiomyoma had an undetermined malignant potential.

Conclusions:

The proportion of malignancy is low after using morcellation in patients who undergo laparoscopic myomectomy. Patients with fast-growing uterine fibroids and abnormal ultrasonic tumor blood flow should be considered for malignant potential, and morcellation should be avoided.

Assisted Hatching in Couples with Advanced Maternal Age: A Systematic Review and Meta-analysis

This systematic review aimed to evaluate the efficacy and safety of assisted hatching (AH) performed in couples with advanced maternal age. We searched for randomized controlled trials (RCTs) in electronic databases, including MEDLINE, EMBASE and CENTRAL (from inception to January 2018); in addition, we hand-searched the reference lists of included studies and similar reviews. We included RCTs comparing AH versus no treatment (control). The meta-analysis was performed by RevMan 5.3 software. The search retrieved 943 records and 8 RCTs were included, comprising 870 cycles (n=440 for AH, and n=430 for control). There was no significant difference in the rates of live birth (RR 0.88, 95% CI 0.65 to 1.18, 3 RCTs, n=427, I²=0%), clinical pregnancy (RR 1.00, 95% CI 0.83 to 1.19, 8 RCTs, n=870, I²=22%), implantation (RR 1.07, 95% CI 0.83 to 1.39, 4 RCTs, n=1359, I²=0%), miscarriage (RR 1.13, 95% CI 0.66 to 1.94, 2 RCTs, n=116, I²=0%) and multiple pregnancy (RR 0.89, 95% CI 0.31 to 2.52, 1 RCT, n=97, I²=not applicable) between the treatment group and control group. No reasonable conclusions could be drawn regarding reproductive outcomes after AH in patients with advanced maternal age due to the small sample pooled in meta-analyses. Studies of high methodological quality and with adequate power are necessary to further investigate the value of AH in assisted conception of those patients.

[IMSI versus ICSI for male factor infertility: A meta-analysis]

OBJECTIVE

To evaluate the efficacy and safety of intracytoplasmic morphologically selected sperm injection (IMSI) versus intracytoplasmic sperm injection (ICSI) in in vitro fertilization (IVF) for couples with male factor infertility.

METHODS

Using the Cochrane system evaluation method, we searched MEDLINE, EMBASE, CENTRAL, ClinicalTrials.gov, and SinoMed and manually searched the reference lists of the included studies and relevant reviews for randomized controlled trials (RCT) comparing ICSI and IMSI published from 1992 to July 2017. We performed a meta-analysis on the included literature with the RevMan 5.3 software and subgroup analyses due to the prominent clinical heterogeneity of the patients.

RESULTS

Of the 280 articles retrieved, 8 RCTs were included, involving 1 741 IVF cycles (842 cycles of IMSI versus 899 cycles of ICSI). There was no evidence for any significant difference between IMSI and ICSI in the live birth rate in the subgroup of infertility induced by pure male factors (RR = 1.31, 95% CI: 0.68－2.51; very low quality evidence from 1 RCT with 77 cycles) but an association of IMSI with an increased clinical pregnancy rate (RR = 1.46, 95% CI: 1.02－2.07; low quality evidence from 4 RCTs with 813 cycles), nor was there any evidence for that in the live birth rate (RR = 0.88, 95% CI: 0.60－1.31; low quality evidence from 1 RCT with 255 cycles) or clinical pregnancy rate (RR = 1.03, 95% CI: 0.86－1.23; moderate quality evidence from 3 RCTs with 851 cycles) in the subgroup of infertility caused by accompanying male factors.

CONCLUSIONS

The evidence is of low quality for the association of IMSI with an increased rate of clinical pregnancy and is not sufficient to support the routine use of IMSI in IVF for male factor infertility.

[Expression of hypoxia-inducible factor 1α in gastric cancer and its clinical signficance]

OBJECTIVE

To explore the expression level and location of hypoxia-inducible factor 1α (HIF-1α) in gastric cancer (GC) tissues and their relationship with clinicopathological features and clinical outcomes.

METHODS

From July to September 2015, 27 pairs of fresh paired GC tissues and adjacent normal tissues were gathered from the Eighth Department of General Surgery of the First Affiliated Hospital of Anhui Medical University. Quantitative real-time PCR (qRT-PCR) and Western blot were performed to detect the expression of HIF-1α mRNA and protein in these tissues. A total of 191 GC tissues and 46 randomly selected adjacent normal gastric tissues were consecutively collected between December 2006 and September 2008 from Department of General Surgery of the same hospital. Immunohistochemistry were performed on them to detect the expression of HIF-1α and CD34[described in terms of microvessel density (MVD)], and correlation of different locations of HIF-1α (in cytoplasm or nucleus) with MVD, clinicopathological features, and clinical prognosis was analyzed.

RESULTS

The average relative expression level of HIF-1α mRNA in GC tissues (0.625±0.170) was significantly higher than in normal adjacent tissues (0.218±0.036, t=2.336, P=0.023) by qRT-PCR. From the results of Western blot, the expression level of HIF-1α protein increased in GC tissues compared with its corresponding normal tissues. Immunohistochemistry results revealed that positive HIF-1α staining was observed in 67.54% GC tissues and 45.65% normal tissues, with significant difference (P=0.006). And 35.08% in GC and 45.65% in normal tissues were cytoplasmic positive (P=0.138); while 37.17% in GC and only 2.17% in normal tissues were nuclear positive, with significant difference (P<0.001). High differentiation group and TNM clinical early stage (Ⅰ+ Ⅱ) group had significantly higher cytoplasmic HIF-1α expression positive rate compared with low differentiation group (P=0.008) and TNM clinical intermediate-advanced stage (Ⅲ+ Ⅳ) group (P=0.019); whereas low differentiation group had significantly higher nuclear HIF-1α expression positive rate compared with high differentiation group (P=0.043). The mean MVD in the nuclear HIF-1α positive GC group (115.6 ± 7.8) was higher than that in the cytoplasmic HIF-1α positive GC group (93.1±7.5, t=2.077, P=0.040). The median follow-up time was 56(3-81)months. Kaplan-Meier survival analysis and Log-Rank test results showed that nuclear HIF-1α positive patients had a shorter survival time (median 45 months) than cytoplasmic HIF-1α positive patients (median 64 months, P<0.001). Multivariate Cox regression analysis revealed that differentiation (HR=1.713; 95% CI: 1.019-2.882), depth of invasion (tumor stage, HR=6.137; 95% CI: 1.832-20.556) and lymph node metastasis (HR=2.788; 95% CI: 1.313-5.920) were independent prognostic factors for GC (all P<0.05).

CONCLUSION

Different location of HIF-1α protein may be realted to the tumorigenesis and progression of GC, and may become a potential prognostic indicator of GC.

The effects of hyaluronic acid vaginal gel on the vaginal epithelium of ovariectomized rats

OBJECTIVE

Hyaluronic acid is one of the best materials of water retention which can be used in vaginal atrophy. This study is to evaluate the role and mechanism of the hyaluronic acid vaginal gel (Hyalofemme) in the vaginal epithelium of ovariectomized rats.

MATERIALS AND METHODS

Sixty SD rats were randomly divided into control group (Sham ovariectomy, Sham-OVX), tendency group (ovariectomy, OVX), and experiment group (ovariectomy+Hyalofemme, OVX+Hyalofemme). The hyaluronic acid vaginal gel was administered local vaginal therapy to the experiment group with cytologicaly confirmed vaginal atrophy. The doses were adjusted by animal weight according to human dosage. After daily treatment for 14 days, VEGF and P-AKT activations were detected by Western blot in the experiment group.

RESULTS

The hyaluronic acid vaginal gel proved to be very effective in the cytological reversal of vaginal atrophy but did not increase uterine weight. Vaginal microecosystem indicators were negative in the control group and the experiment group. By contrast, the indicators were positive in the tendency group.

CONCLUSION

Hyaluronic acid vaginal gel is effective in the reversal of vaginal atrophy and is beneficial for improving vaginal microecosystem in the postmenopausal rat model. The hyaluronic acid vaginal gel can also improve the repair capacity of the vaginal epithelium.

Intense nanosecond pulsed electric fields promote cancer cell apoptosis through centrosome-dependent pathway involving reduced level of PLK1

BACKGROUND

Intense nanosecond pulsed electric fields (nsPEFs) have been known to promote apoptosis without physically changing membrane structure or damaging morphology of tumor cells. To determine the contribution of centrosome to the progression of apoptosis by nsPEFs, HeLa cells were exposed to high intensity (6 kV/cm) nsPEFs (8-32 ns) in normal culture condition and cell biology and molecular parameters of cells were investigated.

MATERIALS AND METHODS

Apoptotic cell death was identified by TUNEL assay after being exposed to the nsPEFs with various pulse durations, while immunofluorescent staining was performed to detect the number and distribution of centrosomes. To clarify whether nsPEFs-induced centrosome over-duplication is the consequence of DNA damage, we used comet assay to detect simultaneous DNA damage. And additionally Western Blot was used to detect PLK1 protein level to explore the correlation between apoptotic cell death and nsPEFs-induced centrosome over-duplication. Correlation between nsPEFs and molecular parameters was statistically analyzed.

RESULTS

NsPEFs induced a clear apoptosis reaching a maximum at 24ns, 24h after exposure (p < 0.05), where DNA fragmentation and over-duplicated centrosomes were observed. This apoptosis may be promoted in a time- and pulse duration-dependent manner. Polo-like kinase (PLK1) protein levels were significantly decreased by such nsPEFs (p < 0.05). Control treatment without the nsPEFs did not cause any damage to the cultured HeLa cells.

CONCLUSIONS

Intense nsPEFs promote cell apoptosis through a centrosome-mediated pathway involving a reduction in the level of PLK1, which may provide new therapeutic targets for human cancer treatment.

[Expression of long non-coding RNA HOTAIR mRNA in ovarian cancer]

OBJECTIVE

To investigate the long non-coding RNA HOTAIR (long non-coding HOX antisense intergenic RNA) by examining HOTAIR expression levels in ovarian cancer tissue and normal ovarian tissue.

METHODS

The mRNA of long non-coding RNA HOTAIR expressions were detected by real-time fluorescence quantitative PCR in ovarian cancer (44) and normal ovary tissues (14).

RESULTS

The expression of HOTAIR in ovarian cancer tissue was higher than that in normal ovarian tissue (1.26 +/- 0.27 vs. 0.14 +/- 0.09, P < 0.05). The expression was statistically higher in poorly differentiated ovarian cancer than poorly-moderately, moderately-well, and well-differentiated ones (1.65 +/- 0.41 vs. 0.39 +/- 0.14, P < 0.05).

CONCLUSION

RNA HOTAIR expressions were higher in ovarian cancer; it may play a role in ovarian cancer, and become a biomarker for malignant degree of ovarian cancer and may provide a novel therapeutic target for ovarian cancer.

[Effects of NF-kappaB inhibitor on cisplatin-induced apoptosis in cervical cancer]

OBJECTIVE

To observe whether cisplatin-induced apoptosis were increased when SiHa cells were preincubated with nuclear factor-kappa B (NF-kappaB) inhibitors [aspirin, sulindac, curcumin or pyrrolidine dithiocarbamate (PDTC)].

METHODS

SiHa cells were preincubated 2 hours with aspirin, sulindac, curcumin and PDTC respectively, then a further incubation were done with cisplatin, and Western blot analysis were applied to detect P65 level of nuclear extraction. MTT assay was done to detect relative cell viability. TUNEL was applied to detect apoptosis rates. Flow cytometryies with PI staining were also used to detect apoptosis as well as cell cycle.

RESULTS

When SiHa cells were pretreated with aspirin, sulindac, curcumin or PDTC, Western blot showed that the expression of P65 was inhibited upon cisplatin stimulus (P < 0.05). MTT assay demonstrated that a preincubation with NF-kappaB inhibitor could signifianctly increase cisplatin-induced chemosensitivity (P < 0.05). When cells pretreated with aspirin, sulindac, curcumin, or PDTC, TUNEL and flow cytometries assay showed that the apoptotic rates were all increased after 24 hours cisplatin stimulus (P < 0.05). Results of flow cytometries were also showed that a pretreation with aspirin, sulindac, curcumin, or PDTC could significantly increase cisplatin-induced apoptosis.

CONCLUSION

Aspirin, sulindac, curcumin and PDTC could all inhibit cisplatin induced NF-kappaB activiation, which could increase cispaltin-induced chemosensativity by augments of apoptosis.

Increased expression of importin13 in endometriosis and endometrial carcinoma

Background

Importin13 (IPO13) is a novel potential marker of corneal epithelial progenitor cells. We investigated the expression and localization of IPO13 in endometrial, endometriotic and endometrial carcinoma tissue.

Material/Methods

IPO13 expression in endometrial, endometriotic and endometrial carcinoma tissue was examined by immunohistochemistry, qPCR and Western blot.

Results

Immunohistochemistry studies showed that IPO13 protein was expressed mainly in cytoplasm of glandular epithelial cell and stromal cells. The rate of importin13-positive cells in proliferative phase endometrium was higher (by about 6-fold) than that in secretory endometrium (P<0.05) and the rate of importin13-positive cells in endometriosis and endometrial carcinoma was higher than that in normal secretory phase endometrial tissues (by about 4- and 9-fold, respectively). Immunofluorescence microscopy revealed co-localization of IPO13 with CD34, CD45, c-kit, telomerase, CD90 and CD146. QPCR revealed significantly increased IPO13 mRNA in endometriosis and endometrial carcinoma versus secretory phase endometrium (by about 2- and 10-fold, respectively). Western blot analysis showed that IPO13 protein is enhanced in endometriosis and endometrial carcinoma versus secretory phase endometrium (p<0.05).

Conclusions

These results demonstrate an increased expression of IPO13 in endometriosis and endometrial carcinoma, which could be involved in the pathogenesis of endometriosis and endometrial carcinoma; IPO13 can serve as an endometrial progenitor/stem cell marker.

Wogonin potentiates cisplatin-induced cancer cell apoptosis through accumulation of intracellular reactive oxygen species

Chemoresistance to cisplatin is a major limitation of cisplatin-based chemotherapy in the clinic. The combination of cisplatin with other agents has been recognized as a promising strategy to overcome cisplatin resistance. Previous studies have shown that wogonin (5,7-dihydroxy-8-methoxyflavone), a flavonoid isolated from the root of the medicinal herb Scutellaria baicalensis Georgi, sensitizes cancer cells to chemotheraputics such as etoposide, adriamycin, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and TNF. However, the effect of wogonin on cisplatin-induced cytotoxicity has not been previously reported. In this study, the non-small cell lung cancer cell line A549 and the cervical cancer cell line HeLa were treated with wogonin or cisplatin individually or in combination. It was found for the first time that wogonin is able to sensitize cisplatin-induced apoptosis in both A549 cells and HeLa cells as indicated by the potentiation of activation of caspase-3, and cleavage of the caspase-3 substrate PARP in wogonin and cisplatin co-treated cells. Importantly, wogonin robustly induced H2O2 accumulation in these cells, which substantially contributes to the sensitization of cisplatin cytotoxicity by wogonin, as two reactive oxygen species scavengers, butylated hydroxyanisole (BHA) and N-acetyl-L-cysteine (NAC), significantly suppressed the potentiated cytotoxicity caused by wogonin and cisplatin co-treatment. The results from this study provide important new evidence supporting the potential use of wogonin as a cisplatin sensitizer for cancer therapy.

Association of an interleukin-16 gene polymorphism with the risk and pain phenotype of endometriosis

Interleukin-16 (IL-16), a proinflammatory cytokine, plays a pivotal role in inflammatory diseases as well as in the pathogenesis of endometriosis. The aim of this study was to evaluate the association of IL-16 gene polymorphisms with the risk and clinical phenotypes of endometriosis in Chinese women. We analyzed rs4778889 T/C, rs11556218 T/G polymorphisms of the IL-16 gene in 230 patients with endometriosis and 203 controls in a Chinese population, using a polymerase chain reaction-high resolution melting analysis strategy and DNA sequencing methods. There was no significant difference in the genotype and allele frequencies of the rs11556218 T/G polymorphism between patients with endometriosis and controls (p>0.05). In contrast, the genotype and allele frequencies of the rs4778889 T/C polymorphism were statistically different between patients with endometriosis and controls, which resulted from a significantly increased proportion of TC heterozygote and CC homozygote carriers among patients with endometriosis (p=0.001 and 0.012, respectively); moreover, further subgroup analysis found that the genotype difference was more evident in patients with endometriosis who also experienced pain symptoms (p<0.001) than in patients without pain symptoms (p=0.625) when compared with controls. Our results suggest that the rs4778889 T/C polymorphism of the IL-16 gene may be associated with risk of endometriosis in the Chinese population, especially in patients with pain phenotype.

[Effects of energy controllable steep pulses on intracellular calcium concentration and cell membrane potential]

BACKGROUND AND OBJECTIVE

Our previous experiments showed that steep pulses could kill tumor cells, but the mechanism is unclear. This study was to probe the effects of different dosages of energy controllable steep pulses (ECSP) on intracellular concentration of dissociative calcium ion ([Ca2+]i) and cell membrane potential.

METHODS

The breast carcinoma MDA-MB-231 cells were divided into control group and five ECSP (different dosages) groups. Ca2+ was labeled by Fluo-3/AM and cell membrane potential was labeled by DiBAC4(3). The mean fluorescence intensity in MDA-MB-231 cells was observed by laser confocal microscopy after ECSP treatment. The changes of calcium concentration and cell membrane potential after ECSP treatment were analyzed. The changes of intracellular [Ca2+]i after ECSP treatment were also observed either with or without Ca2+ outside of the cells.

RESULTS

Ca2+ outflow was observed when the cells were treated with lower dosage of pulse in quiet state; the outflow was enhanced with the dosage increase. In real-time kinetic detection, intracellular Ca2+ concentration was increased with the increase of pulse electric field intensity when cells were treated with lower dosages of ECSP. When the voltage was 285 V, frequency was 100 Hz, [Ca2+]i decreased obviously. The intracellular Ca2+ concentration was obviously lower in the cells without outside Ca2+ than in cells with outside Ca2+, but it still increased gradually. Low dosage of ECSP induced the increase of cell membrane potential, indicating the depolarization of cell membrane. With increase of the dosage, cell membrane potential was attenuated, indicating the superpolarization of cell membrane.

CONCLUSION

Lower dosage of ECSP can induce the depolarization of cell membrane and the inflow of outside Ca2+; higher dosage of ECSP can directly destroy the cell membrane and induce the superpolarization of cell membrane, then induce the outflow of intracellular Ca2+ which causes the necrosis of tumor cells.

The effect of high frequency steep pulsed electric fields on in vitro and in vivo antitumor efficiency of ovarian cancer cell line skov3 and potential use in electrochemotherapy

BACKGROUND

Patients received electrochemotherapy often associated with unpleasant sensations mainly result from low-frequency electric pulse induced muscle contractions. Increasing the repetition frequency of electric pulse can reduce unpleasant sensations. However, due to the specificity of SPEF, frequency related antitumor efficiency need to be further clarified. The aim of this study was to compare in vitro cytotoxic and in vivo antitumor effect on ovarian cancer cell line SKOV3 by SPEF with different repetition frequencies. Explore potential benefits of using high frequency SPEF in order to be exploitable in electrochemotherapy.

METHODS

For in vitro experiment, SKOV3 cell suspensions were exposed to SPEF with gradient increased frequencies (1, 60, 1000, 5000 Hz) and electric field intensity (50, 100, 150, 200, 250, 300, 350, 400 V/cm) respectively. For in vivo test, SKOV3 subcutaneous implanted tumor in BALB/c nude mice (nu/nu) were exposure to SPEF with gradient increased frequencies (1, 60, 1000, 5000 Hz) and fixed electric field intensity (250 V/cm) (7 mice for each frequency and 7 for control). Antitumor efficiency was performed by in vitro cytotoxic assay and in vivo tumor growth inhibition rate, supplemented by histological and TEM observations. Data were analyzed using one-way ANOVA followed by the comparisons of multiple groups.

RESULTS

SPEF with a given frequency and appropriate electric field intensity could achieve similar cytotoxicity until reached a plateau of maximum cytotoxicity (approx. 100%). SPEF with different frequencies had significant antitumor efficiency in comparison to the control group (P < 0.05). However, there was no difference in tumor responses among test groups (P > 0.05). Histological and TEM observations demonstrated obvious cell damages in response to SPEF exposure. Furthermore, SPEF with 5 kHz could induce apoptosis under TEM observations both in vitro and in vivo.

CONCLUSION

SPEF with high frequency could also achieve similar antitumor efficiency which can be used to reduce unpleasant sensations in tumor electrical treatment. Our research proposed potential applications of using high frequency SPEF in clinical cancer treatment.

[Impacts of steep pulsed electric fields on lymphatic capillaries in VX2 implanted breast cancer in rabbits]

BACKGROUND & OBJECTIVE

Electrochemotherapy mediated by electric pulse has become a multidisciplinary biomedical engineering technique in modern medical science. Its main mechanisms are enhancing the diffusion of chemotherapeutic drugs, antibodies, or genes into the inner part of tumor cells mediated by membrane-electropermeabilization caused by electric pulse. Our previous studies confirmed that steep pulsed electric field (SPEF) could irreversibly cause membrane electropermeabilization, and lead to death of tumor cells. This study was to explore the acute killing effects of SPEF on lymphatic capillaries in VX2 implanted breast cancer in rabbits.

METHODS

Tumor model of VX2 implanted breast cancer was successfully established in rabbits. Isosulfan blue staining, 5'-AMP-ALPase enzymohistochemical double staining, and electron microscopy was used to observe the morphologic changes of local lymphatic capillaries around cancer tissues exposed to SPEF.

RESULTS

After exposed to SPEF, no lymphatic vessels were found with isosulfan blue staining, only blurred structures were observed; enzymohistochemistry showed no positively stained lymphatic vessels, only fragmental structures around cancer tissues were observed; integrity and continuity of lymphatic endothelium were destroyed under transmission electron microscope.

CONCLUSION

SPEF has the potential to destroy lymphatic capillaries around VX2 implanted breast cancer, and can decrease the possibility of post-treatment lymphatic metastasis.

Retinopathy in a Chinese population with type 2 diabetes: factors affecting the presence of this complication at diagnosis of diabetes

This study examined the prevalence of retinopathy in 2131 patients with type 2 diabetes attending a Beijing hospital for the first time. The median age of patients was 58 years (IQR 50-65). The overall prevalence of retinopathy was 27.3% (95% CI: 25.4-29.2) and for proliferative retinopathy 7.8% (95% CI: 6.7-8.9). When all patients were considered together, duration of diabetes (OR=1.8; P=0.001) and albumin excretion rate (OR=1.5; P=0.019) were independent risk factors for retinopathy. Blue-collar occupation (OR=1.5; P=0.047) and blood pressure (OR=1.2; P=0.021) were additional risk factors for non-proliferative and proliferative retinopathy respectively. Amongst the 773 newly diagnosed patients, 21% (95% CI: 17.8-23.6) already had retinopathy. The median age of those patients with retinopathy at diagnosis of diabetes was 3 years higher that those without retinopathy, and blue-collar workers (OR=2.2; P=0.012) as well as female gender were particularly at risk (OR=2.0; P=0.033). There was a strong correlation between duration of diabetes with the presence of retinopathy (r=0.95; P=0.01). By extrapolation, it could be estimated that some degree of hyperglycaemia might have been present for more than 20 years before diabetes was diagnosed. These findings emphasise the importance of earlier diagnosis of diabetes and its complications, especially in socially disadvantaged groups.

[Tumor necrosis factor in peritoneal fluid of infertile women with endometriosis and its relation to sperm motility]

Tumor necrosis factor (TNF) of 16 infertile women with endometriosis was measured in their peritoneal fluid (PF) with double monoclonal antibody ELISA method, and its effect on sperm motility and membrane integrity was evaluated by semen analysis and hypoosmotic swelling test (HOS). Comparing with that of infertile women without endometriosis (n = 11) and normal fertile women (n = 7), the level of PF-TNF was significantly higher in women with endometriosis (P < 0.01), in accord with the stage of the disease. In the PF of these patients after incubation with the donor sperms, the percentages of forward movement, total motility and hypoosmotic swelling of the donor sperms were significantly decreased (P < 0.01), showing a negative correlation to TNF levels. These results indicate that the elevation of PF-TNF in endometriosis has detrimental effect on sperm function.