Serum semaphorin 4C as a diagnostic biomarker in breast cancer: A multicenter retrospective study.

BACKGROUND: To date, there is no approved blood-based biomarker for breast cancer detection. Herein, we aimed to assess semaphorin 4C (SEMA4C), a pivotal protein involved in breast cancer progression, as a serum diagnostic biomarker. METHODS: We included 6,213 consecutive inpatients from Tongji Hospital, Qilu Hospital, and Hubei Cancer Hospital. Training cohort and two validation cohorts were introduced for diagnostic exploration and validation. A pan-cancer cohort was used to independently explore the diagnostic potential of SEMA4C among solid tumors. Breast cancer patients who underwent mass excision prior to modified radical mastectomy were also analyzed. We hypothesized that increased pre-treatment serum SEMA4C levels, measured using optimized in-house enzyme-linked immunosorbent assay kits, could detect breast cancer. The endpoints were diagnostic performance, including area under the receiver operating characteristic curve (AUC), sensitivity, and specificity. Post-surgery pathological diagnosis was the reference standard and breast cancer staging followed the TNM classification. There was no restriction on disease stage for eligibilities. RESULTS: We included 2667 inpatients with breast lesions, 2378 patients with other solid tumors, and 1168 healthy participants. Specifically, 118 patients with breast cancer were diagnosed with stage 0 (5.71%), 620 with stage I (30.00%), 966 with stage II (46.73%), 217 with stage III (10.50%), and 8 with stage IV (0.39%). Patients with breast cancer had significantly higher serum SEMA4C levels than benign breast tumor patients and normal controls (P < 0.001). Elevated serum SEMA4C levels had AUC of 0.920 (95% confidence interval [CI]: 0.900-0.941) and 0.932 (95%CI: 0.911-0.953) for breast cancer detection in the two validation cohorts. The AUCs for detecting early-stage breast cancer (n = 366) and ductal carcinoma in situ (n = 85) were 0.931 (95%CI: 0.916-0.946) and 0.879 (95%CI: 0.832-0.925), respectively. Serum SEMA4C levels significantly decreased after surgery, and the reduction was more striking after modified radical mastectomy, compared with mass excision (P < 0.001). The positive rate of enhanced serum SEMA4C levels was 84.77% for breast cancer and below 20.75% for the other 14 solid tumors. CONCLUSIONS: Serum SEMA4C demonstrated promising potential as a candidate biomarker for breast cancer diagnosis. However, validation in prospective settings and by other study groups is warranted.

Efficacy analysis of medical and surgical treatments in chronic kidney disease patients with secondary hyperparathyroidism.

PURPOSE: To investigate the effects of surgical and medical treatments on chronic kidney disease (CKD) patients with secondary hyperparathyroidism (SHPT). MATERIALS AND METHODS: A total of 198 CKD patients with SHPT were identified at Tongji Hospital from January 2013 to June 2017. RESULTS: Surgical group (53 patients) received maintenance dialysis for 78.0 ±â€¯4.9 months, while medical group (84 patients) for 62.0 ±â€¯6.4 months. The serum intact parathyroid hormone (iPTH) in surgical group reduced apparently compared with medical group (P = 0.015) and maintained satisfied result during three years of follow-up (67.4 ±â€¯7.4 pg/ml). The recurrence rate in surgical group was 7.5% and in medical group was 15.5% (P = 0.024). Beyond that, 5 (5.9%) patients suffered persistent hyperparathyroidism in medical group. CONCLUSION: Although the progress of medical treatment is changing rapidly, surgical treatment is still an effective way to control serum iPTH and calcium chronically for SHPT patients. Complex SHPT patients can also receive satisfied effect by surgical treatment, without apparently increasing the risk of complications.

Transmembrane TNF-alpha promotes chemoresistance in breast cancer cells.

Chemoresistance remains a major obstacle to successful treatment of breast cancer. Although soluble tumor necrosis factor-α (sTNF-α) has been implicated in mediating drug-resistance in human cancers, whether transmembrane tumor necrosis factor-α (tmTNF-α) plays a role in chemoresistance remains unclear. Here we found that over 50% of studied patients expressed tmTNF-α at high levels in breast cancer tissues and tmTNF-α expression positively correlated with resistance to anthracycline chemotherapy. Alteration of tmTNF-α expression changed the sensitivity of primary human breast cancer cells and breast cancer cell lines to doxorubicin (DOX). Overexpression of N-terminal fragment (NTF) of tmTNF-α, a mutant form with intact intracellular domain of tmTNF-α to transmit reverse signals, induced DOX-resistance. Mechanistically, the tmTNF-α/NTF-ERK-GST-π axis and tmTNF-α/NTF-NF-κB-mediated anti-apoptotic functions were required for tmTNF-α-induced DOX-resistance. In a xenograft mouse model, the combination of tmTNF-α suppression with chemotherapy significantly enhanced the efficacy of DOX. Our data indicate that tmTNF-α mediates DOX-resistance through reverse signaling and targeting tmTNF-α may be beneficial for the treatment of DOX-resistant breast cancer.

An anti-cancer WxxxE-containing azurin polypeptide inhibits Rac1-dependent STAT3 and ERK/GSK-3ß signaling in breast cancer cells.

In our previous study, we characterized a mycoplasmal small GTPase-like polypeptide of 240 amino acids that possesses an N-terminal WVLGE sequence. The N-terminal WVLGE sequence promotes activation of Rac1 and subsequent host cancer cell proliferation. To investigate the function of the WxxxE motif in the interaction with Rac1 and host tumor progression, we synthesized a 35-amino acid WVLGE-containing polypeptide derived from a cell-penetrating peptide derived from the azurin protein. We verified that the WVLGE-containing polypeptide targeted MCF-7 cells rather than MCF-10A cells. However, the WVLGE-containing polypeptide inhibited activation of Rac1 and induced cellular phenotypes that resulted from inhibition of Rac1. In addition, the WVLGE-containing polypeptide down-regulated phosphorylation of the STAT3 and ERK/GSK-3ß signaling pathways, and this effect was abolished by either stimulation or inhibition of Rac1 activity. We also found that the WVLGE-containing polypeptide has a Rac1-dependent potential to suppress breast cancer growth in vitro and in vivo. We suggest that by acting as a Rac1 inhibitor, this novel polypeptide may be useful for the treatment of breast cancer.

Anti-RhoC siRNAs inhibit the proliferation and invasiveness of breast cancer cells via modulating the KAI1, MMP9, and CXCR4 expression.

Overexpression of RhoC in breast cancer cells indicates poor prognosis. In the present study, we aim to investigate the possible antitumor effects of anti-RhoC small-interfering RNA (siRNA) in inflammatory breast cancer cells. In this study, a specific anti-RhoC siRNA was used to inhibit RhoC synthesis. Transfection of anti-RhoC siRNA into two IBC cells SUM149 and SUM190 induced extensive degradation of target mRNA and led to significant decrease in the synthesis of protein. Anti-RhoC siRNA inhibited cell proliferation and invasion, increased cell apoptosis, and induced cell cycle arrest in vitro. Moreover, the transfection of siRNA increased the expression of KAI1 and decreased the expression of MMP9 and CXCR4 in both mRNA and protein levels. Furthermore, transplantation tumor experiments in BALB/c-nu mice showed that intratumoral injection of anti-RhoC siRNA inhibited tumor growth and increased survival rate. Our results suggested that RhoC gene silencing with specific anti-RhoC siRNA would be a potential therapeutic method for metastatic breast cancer.

Fibroblast-Derived Exosomes Contribute to Chemoresistance through Priming Cancer Stem Cells in Colorectal Cancer.

Chemotherapy resistance observed in patients with colorectal cancer (CRC) may be related to the presence of cancer stem cells (CSCs), but the underlying mechanism(s) remain unclear. Carcinoma-associated fibroblasts (CAFs) are intimately involved in tumor recurrence, and targeting them increases chemo-sensitivity. We investigated whether fibroblasts might increase CSCs thus mediating chemotherapy resistance. CSCs were isolated from either patient-derived xenografts or CRC cell lines based on expression of CD133. First, CSCs were found to be inherently resistant to cell death induced by chemotherapy. In addition, fibroblast-derived conditioned medium (CM) promoted percentage, clonogenicity and tumor growth of CSCs (i.e., CD133+ and TOP-GFP+) upon treatment with 5-fluorouracil (5-Fu) or oxaliplatin (OXA). Further investigations exhibited that exosomes, isolated from CM, similarly took the above effects. Inhibition of exosome secretion decreased the percentage, clonogenicity and tumor growth of CSCs. Altogether, our findings suggest that, besides targeting CSCs, new therapeutic strategies blocking CAFs secretion even before chemotherapy shall be developed to gain better clinical benefits in advanced CRCs.

A prospective, randomized study on hepatotoxicity of anastrozole compared with tamoxifen in women with breast cancer.

Tamoxifen and anastrozole are widely used as adjuvant treatment for early stage breast cancer, but their hepatotoxicity is not fully defined. We aimed to compare hepatotoxicity of anastrozole with tamoxifen in the adjuvant setting in postmenopausal breast cancer patients. Three hundred and fifty-three Chinese postmenopausal women with hormone receptor-positive early breast cancer were randomized to anastrozole or tamoxifen after optimal primary therapy. The primary end-point was fatty liver disease, defined as a liver-spleen ratio <0.9 as determined using a computed tomography scan. The secondary end-points included abnormal liver function and treatment failure during the 3-year follow up. The cumulative incidence of fatty liver disease after 3 years was lower in the anastrozole arm than that of tamoxifen (14.6% vs 41.1%, P < 0.0001; relative risk, 0.30; 95% CI, 0.21-0.45). However, there was no difference in the cumulative incidence of abnormal liver function (24.6% vs 24.7%, P = 0.61). Interestingly, a higher treatment failure rate was observed in the tamoxifen arm compared with anastrozole and median times to treatment failure were 15.1 months and 37.1 months, respectively (P < 0.0001; HR, 0.27; 95% CI, 0.20-0.37). The most commonly reported adverse events were 'reproductive system disorders' in the tamoxifen group (17.1%), and 'musculoskeletal disorders' in the anastrozole group (14.6%). Postmenopausal women with hormone receptor-positive breast cancer receiving adjuvant anastrozole displayed less fatty liver disease, suggesting that this drug had a more favorable hepatic safety profile than tamoxifen and may be preferred for patients with potential hepatic dysfunction.

Synergism between upregulation of Rab7 and inhibition of autophagic degradation caused by mycoplasma facilitates intracellular mycoplasma infection.

Following fusion of a mycoplasma with a host cell membrane, the inserted components of mycoplasma may then be transported through the endocytic pathway. However, the effects of mycoplasmas on the host cell endomembrane system are largely unknown. In this study, mycoplasma­induced changes in the dynamics of endocytic and autophagic systems were investigated. Endocytosis and autophagy are two major processes involved in the survival of intracellular prokaryotic pathogens. It was found that, immediately following infection, mycoplasmas induce endocytosis in the host cell; however, in the long term the mycoplasmas suppress turnover of the components of the endocytic pathway. Immunofluorescence microscopy revealed that Rab7 and LC3­II are recruited to the intracellular mycoplasma­containing compartments. Western blot analysis and quantitative reverse transcription-polymerase chain reaction (qPCR) showed that mycoplasmas increase expression of Rab7 by upregulating transcription, but increase levels of LC3­II and p62 by post­translational regulation. Furthermore, it was demonstrated that mycoplasma infection causes inhibition of autophagic degradation of LC3­II and p62. In addition, it was found that upregulation of Rab7 and inhibition of autophagic degradation synergistically contributes to intracellular mycoplasma accumulation. In conclusion, these findings suggest that mycoplasmas may manipulate host cell endosomal and autophagic systems in order to facilitate intracellular infection.

A small GTPase­like protein fragment of Mycoplasma promotes tumor cell migration and proliferation in vitro via interaction with Rac1 and Stat3.

The Mycoplasma genus comprises a group of microbes that cause persistent infection in humans and its role in promoting tumor development has long been a concern. Although mixtures of components isolated from Mycoplasma have been shown to activate host Rho family small GTPases and Stat3, no individual factor with this activity has been reported. In the current study, a conserved small GTPase-like protein fragment (SGLP) from Mycoplasma pulmonis chromosome partition protein, Smc, was identified as a virulence factor. SGLP was observed to interact with Rac1 and Stat3. The wild­type (wt) SGLP, which contains a WxxxE motif, induced activation of Rac1 and phosphorylation of Stat3 at the tyrosine­705 residue, while the SGLP mutant containing a mutation from WxxxE to AxxxA did not exert the same effects. Moreover, SGLP­induced Stat3 phosphorylation was observed to be dependent upon Rac1 activity. Furthermore, wt SGLP was observed to promote cell migration and increase bromodeoxyuridine incorporation in HeLa cells and the SGLP mutant did not elicit these effects in HeLa cells. In conclusion, the current observations suggest that SGLP is an important virulence factor of Mycoplasma, which contributes to tumor cell migration and proliferation in vitro via interaction with Rac1 and Stat3.

Correlation of cytotoxic effect of transmembrane and secretory TNF-α to cell cycle.

This study was aimed to examine the correlation of the cytotoxic effects induced by two types of TNF-α to cell cycle. Hoechst 33342 and PI were used to detect the morphological changes in the cell death induced by the two types of TNF-α. TdT and PI co-staining was performed to determine the phase of cell cycle of apoptotic cells. L929 cells in different phases of cell cycle were further synchronized and their sensitivity to the two types of TNF-α was observed. Our results showed that the apoptosis of HepG2 cells triggered by tm-TNF-α mainly occurred in G(1) phase while in HL-60, Raji and K562 cell lines it mainly took place in S phase. The apoptosis of L929 cells induced by tm-TNF-α mainly occurred in S phase while the apoptosis induced by s-TNF-α mainly appeared in G(1) phase. L929 cells were sensitive to s-TNF-α when synchronized in G(1) phase (cytotoxicity 49.8%) while their sensitivity to tm-TNF-α was highest in S phase (45.7%) and G(1)/S phase (cytotoxicity 40.6%). It was concluded that tm-TNF-α-induced apoptosis of different target cells took place in different phases of cell cycle. The apoptosis of the specific cell line induced by the two types of TNF-α occurred in different phases of cell cycle. The sensitivity of the specific cell line to the two types of TNF-α was correlated with the phase of cell cycle.

Effects of mitofusin-2 gene on cell proliferation and chemotherapy sensitivity of MCF-7.

In order to evaluate the effect of mitofusin-2 gene (mfn2) on proliferation and chemotherapy sensitivity of human breast carcinoma cell line MCF-7 in vitro, pEGFPmfn2 plasmid carrying full length of mitofusin-2 gene was transfected, by using sofast, into MCF-7 cells. Mitofusin-2 gene expression in MCF-7 cells transfected by sofast after 48 h was detected by PCR and Western blotting, and the stable expression of GFP protein in MCF-7 cells by Western blot analysis. The proliferation of MCF-7 cells was assayed by MTT and cell counting. By using PI method, the effects of mfn2 on the cell cycle distribution of MCF-7 were measured. Annexin-V/PI double labeling method was employed to detect the changes in apoptosis induced by chemotherapeutics before and after transfection. The results showed that the MCF-7 cells transfected with mfn2 gene could stably and highly express GFP protein. MTT assay revealed that after transfection of mfn2 cDNA, the proliferation of MCF-7 cells was significantly inhibited. DNA histogram showed that cells arrested in S phase, and the percentage of S phase cells was 42.7, 17.2 and 19.6 in mfn2 cDNA transfection group, blank plasmid transfection group and blank control group, respectively (P<0.05). The apoptosis ratio of the cells transfected with mfn2 gene was increased from 3.56% to 15.95%, that of the cells treated with camptothecin (CAMP) followed by mfn2 gene transfection was 69.6%, and that in blank plasmid transfection group and blank control group was 31.0% and 23.4% respectively (P<0.05). It was suggested that transfection of mfn2 gene could significantly inhibit the proliferation of MCF-7 cells and promote their sensitivity to CAMP with a synergic effect.

Effects of Mitofusin-2 Gene on Cell Proliferation and Chemotherapy Sensitivity of MCF-7 / 华中科技大学学报（医学）（英德文版）

In order to evaluate the effect of mitofusin-2 gene (mfn2) on proliferation and chemotherapy sensitivity of human breast carcinoma cell line MCF-7 in vitro, pEGFPmfn2 plasmid carrying full length of mitofusin-2 gene was transfected, by using sofast, into MCF-7 cells. Mitofusin-2 gene expression in MCF-7 cells transfected by sofast after 48 h was detected by PCR and Western blotting, and the stable expression of GFP protein in MCF-7 cells by Western blot analysis. The proliferation of MCF-7 cells was assayed by MTT and cell counting. By using PI method, the effects of mfn2 on the cell cycle distribution of MCF-7 were measured. Annexin-V/PI double labeling method was em- ployed to detect the changes in apoptosis induced by chemotherapeutics before and after transfection. The results showed that the MCF-7 cells transfected with mfn2 gene could stably and highly express GFP protein. MTT assay revealed that after transfection of mfn2 eDNA, the proliferation of MCF-7 cells was significantly inhibited. DNA histogram showed that cells arrested in S phase, and the per- centage of S phase cells was 42.7, 17.2 and 19.6 in mfn2 cDNA transfection group, blank plasmid transfection group and blank control group, respectively (P<0.05). The apoptosis ratio of the cells transfected with mfn2 gene was increased from 3.56% to 15.95%, that of the cells treated with camptothecin (CAMP) followed by mfn2 gene transfection was 69.6%, and that in blank plasmid transfection group and blank control group was 31.0% and 23.4% respectively (P<0.05). It was suggested that transfection of mfn2 gene could significantly inhibit the proliferation of MCF-7 cells and pro- mote their sensitivity to CAMP with a synergic effect.

[Effects of mitofusin-2 gene on proliferation and chemosensitivity of human breast carcinoma cell line MCF-7].

BACKGROUND & OBJECTIVE: Mitofusin-2(mfn2), a proliferation-inhibiting gene, targets to the outer membrane of mitochondria. Its overexpression suppresses the proliferation of vascular smooth muscle cells. This study was to explore the effects of mfn2 gene on the proliferation and chemosensitivity of human breast carcinoma cell line MCF-7. METHODS: Plasmid pEGFP-mfn2 containing mfn2 cDNA was constructed and transfected into MCF-7 cells by sofast. The expression of green fluorescent protein (GFP) in MCF-7 cells was detected by Western blot. Cell proliferation was measured by MTT assay and cell counting. Cell cycle and chemosensitivity of MCF-7 cells to camptothecin (CAM) was observed by flow cytometry (FCM). RESULTS: After transfection of pEGFP-mfn2, the stable expression of GFP protein was detected in MCF-7 cells, and cell cycle was arrested: the S phase proportion was significantly higher in pEGFP-mfn2-transfected cells than in pEGFP-transfected and untransfected cells [(42.7+/-1.3)% vs. (17.2+/-2.0)% and (19.6+/-1.7)%, P<0.05]. The apoptosis rate were significantly higher in pEGFP-mfn2-transfected cells than in pEGFP-transfected and untransfected cells [(16.0+/-0.3)% vs. (4.5+/-0.9)% and (3.6+/-0.6)% before treatment of CAM, P<0.05; (69.6+/-4.3)% vs. (31.0+/-1.8)% and (23.4+/-2.8)% after 4-hour treatment of CAM, P<0.05]. CONCLUSION: mfn2 gene can inhibit the proliferation of MCF-7 cells and increase their chemosensitivity to CAM.

[Effect of mitofusin-2 gene in apoptosis of human breast carcinoma cell line in vitro].

OBJECTIVE: To investigate the role of mitofusin-2 gene (mfn2) in apoptosis in human breast carcinoma cell line MCF-7 cells after in vitro transfection. METHODS: pEGFP mfn2 was transfected by sofast in vitro. Expression of GFP was observed by Western blot, and the MCF-7 cell proliferation was measured by MTT and cell counting. Apoptosis in MCF-7 cells was observed in annexin-V/PI and chondrosome transmembrane potential of MCF-7 marked in JC-1 by FCM. The Ultrastructure of cells was observed by transmission electron microscopy. RESULTS: The stable expression of GFP in MCF-7 cells was confirmed by Western blot. Mfn2 significantly inhibited cell proliferation, revealed by MTT, and decrease chondrosome transmembrane potential. Exogenous mfn2 gene significantly induced apoptosis. The apoptotic rate was increased from 3.6% to 16.0% (P < 0.05). Mfn2 gene induced break down and loss of mitochondrial cristae, and rarefaction of mitochondrial ground substance. Swollen mitochondria intensely aggregated around the cell nuclei. CONCLUSION: Mfn2 can strongly induce apoptosis in MCF-7 cells, which may be associated with decrease of mitochondrial transmembrane potential.