UBE2Q1 expression in human colorectal tumors and cell lines

Colorectal cancer is the third most common cancer in the world. Ubiquitin–proteasome system has shown to be activated in colorectal and other malignancies. UBE2Q1 is a novel human gene that encodes a putative E2 ubiquitin conjugating enzyme. Here, we investigated the expression pattern of UBE2Q1 gene in cell lines and tissues from human colorectal tumors. Quantitative (q) RT-PCR were employed to evaluate the expression levels of the mRNA for UBE2Q1 in colorectal cancer cell lines (HT29/219, LS180, SW742, Caco2, HTC116, SW48, SW480 and SW1116). Expression of UBE2Q1 at the protein levels were assessed by Western blotting in cell lines as well as in 43 human colorectal tumor tissues. All cell lines tested expressed UBE2Q1 gene at the level of both mRNA and protein, with the SW1116 line representing the lowest level of expression. The cell lines HT29/219 and SW742 showed the highest levels of UBE2Q1 protein and mRNA respectively. When compared to corresponding normal tissues, malignant parts of colorectal tumors showed increased levels of UBE2Q1 immunoreactivity in 32 (74.42 %) of cases. These data suggest that UBE2Q1 is differentially expressed in colorectal cell lines and shows overexpression in colorectal tumors.     

Protein kinase D1 regulates ERα‐positive breast cancer cell growth response to 17β‐estradiol and contributes to poor prognosis in patients

About 70% of human breast cancers express and are dependent for growth on estrogen receptor α (ERα), and therefore are sensitive to antiestrogen therapies. However, progression to an advanced, more aggressive phenotype is associated with acquisition of resistance to antiestrogens and/or invasive potential. In this study, we highlight the role of the serine/threonine‐protein kinase D1 (PKD1) in ERα‐positive breast cancers. Growth of ERα‐positive MCF‐7 and MDA‐MB‐415 human breast cancer cells was assayed in adherent or anchorage‐independent conditions in cells overexpressing or depleted for PKD1. PKD1 induces cell growth through both an ERα‐dependent manner, by increasing ERα expression and cell sensitivity to 17β‐estradiol, and an ERα‐independent manner, by reducing cell dependence to estrogens and conferring partial resistance to antiestrogen ICI 182,780. PKD1 knockdown in MDA‐MB‐415 cells strongly reduced estrogen‐dependent and independent invasion. Quantification of PKD1 mRNA levels in 38 cancerous and non‐cancerous breast cell lines and in 152 ERα‐positive breast tumours from patients treated with adjuvant tamoxifen showed an association between PKD1 and ERα expression in 76.3% (29/38) of the breast cell lines tested and a strong correlation between PKD1 expression and invasiveness (P < 0.0001). In tamoxifen‐treated patients, tumours with high PKD1 mRNA levels (n = 77, 50.66%) were significantly associated with less metastasis‐free survival than tumours with low PKD1 mRNA expression (n = 75, 49.34%; P = 0.031). Moreover, PKD1 mRNA levels are strongly positively associated with EGFR and vimentin levels (P < 0.0000001). Thus, our study defines PKD1 as a novel attractive prognostic factor and a potential therapeutic target in breast cancer.     

Assessment of RNA in human breast tissue sampled by random periareolar fine needle aspiration and ductal lavage and processed as fixed or frozen specimens

Ductal lavage (DL) and random periareolar fine needle aspiration (RPFNA) have both been proposed as minimally invasive techniques to sample breast tissue during breast cancer prevention trials. Laser capture microdissection (LCM), linear RNA amplification and quantitative real-time polymerase chain reaction (qPCR) theoretically overcome the limitations of small specimen size obtained with DL and RPFNA. In order to test the yield, relative stability and amplifiability of RNA from fixed and archived RPFNA and DL specimens, breast tissue was sampled from individual high risk women (n = 9) by both DL and RPFNA. RPFNA samples showed good RNA/cDNA yield and amplification while only 2 of 9 of the paired DL specimens had cDNA of adequate quality for subsequent PCR. One and two rounds of linear amplification provided approximately a 200- and 20,000-fold enrichment of RNA, respectively. PCR analysis consistently detected ER and COX-1 mRNA in the majority of RPFNA samples examined while pS2, PCNA, VEGF and survivin expression varied with subject. RNA yield and/or stability was greater for fixed and archived RPFNA than DL specimens of breast tissue. In a subsequent study examining an expanded biomarker gene panel in fixed vs. frozen RPFNA samples, mRNA profiles and ranked relative mRNA abundance were similar (r = 0.89) for frozen and fixed RPFNA specimens. In summary, frozen RPFNA samples may be optimal for RNA endpoints in human breast cancer prevention trials but fixed RPFNA specimens allow similar analyses with greater convenience.     

Clinical implications for BRCA gene mutation in breast cancer

To investigate the mutations of BRCA1 and BRCA2 and determine whether clinic-pathological factors related to BRCA gene mutation. Mastectomy specimens from 360 breast cancers were enrolled and examined in the study. The relationship between BRCA gene mutation and clinic-pathological factors was evaluated. Overall, 280 patients were BRCA negative and 80 got BRCA gene mutation. Triple-negative breast cancers—i.e., breast cancers that do not express estrogen receptors (ER), progesterone receptors (PR) or human epidermal growth factor receptor 2 (HER2/neu)—was observed in 53.85% of the BRCA1 mutation patients, in 28.57% of the BRCA2 mutation cases, while 14.29% of BRCA negative patients. BRCA1 mutation patients got a heavy lymph node metastasis and higher nuclear grade tumors than the others (P = 0.004, 0.007). Furthermore, BRCA mutation was also found to be significantly related to ER, PR and HER2/neu status (P < 0.05). BRCA1 expression was not associated with breast cancer-specific survival in the triple-negative breast cancers (P = 0.742). After Cox regression, BRCA1 mutation was not shown to be an independent prognostic factor for breast cancer. These findings substantiated the possibility of tumors associated with BRCA1 mutations divided into two distinct groups, triple-negative and non-triple-negative groups requires further investigation.     

Leisure-time physical activity is associated with reduced risks of breast cancer and triple negative breast cancer in Nigerian women

BackgroundLeisure-time physical activity(LTPA) is associated with a reduced risk of breast cancer, but this has less been investigated by cancer subtypes in Africans living in Sub-Saharan Africa(SSA). We examined the associations between LTPA and breast cancer including its subtypes in Nigerian women and explored the effect modification of body size on such associations.MethodsThe sample included 508 newly diagnosed primary invasive breast cancer cases and 892 controls from the Nigerian Integrative Epidemiology of Breast Cancer(NIBBLE) Study. Immunohistochemical(IHC) analysis was available for 294 cases. Total metabolic equivalents(METs) per hour/week of LTPA were calculated and divided by quartiles(Q1 <3.75, Q2:3.75–6.69, Q3:6.70–14.74, Q4:14.75 ≤). We applied logistic regressions to estimate the adjusted Odds Ratios(ORs) between LTPA and breast cancer and by its molecular subtypes and whether age-adjusted associations are modified by BMI.ResultsThe mean age(Mean±SD) of cases vs. controls(45.5 ± 11.1vs.40.1 ± 9.0) was higher, and the mean total METs hour/week was higher in controls vs. cases(11.9 ± 14.9vs.8.3 ± 11.1,p-value<0.001). Overall, 43.2%(N = 127/294) were classified as HRP, and 41.8%(N = 123/294) as TNBC. Women in the higher LTPA quartiles(Q3-Q4) vs. Q1 had lower odds of having breast cancer(OR_Q4vs.Q1=0.51,95%CI:0.35–0.74) and TNBC(OR_Q4vs.Q1=0.51, 95%CI:0.27–0.96), but not HRP(OR_Q4vs.Q1=0.61,95%CI:0.34–1.09) after adjusting for age, age at first menarche, body size, breastfeeding, menopausal, parity, contraceptives, demographics, alcohol, smoking, and physical activity at home and work. Lastly, LTPA and its age-adjusted association with breast cancer was more pronounced in women with BMI< 30 vs. BMI 30 + .ConclusionsLTPA may reduce the risk of breast cancer, especially TNBC, which is the more aggressive and prevalent molecular subtype of breast cancer in SSA.     

Epstein-Barr Virus,Human Papillomavirus and Mouse Mammary Tumour Virus as Multiple Viruses in Breast Cancer

Background

The purpose of this investigation is to determine if Epstein Barr virus (EBV), high risk human papillomavirus (HPV), and mouse mammary tumour viruses (MMTV) co-exist in some breast cancers.

Materials and Methods

All the specimens were from women residing in Australia. For investigations based on standard PCR, we used fresh frozen DNA extracts from 50 unselected invasive breast cancers. For normal breast specimens, we used DNA extracts from epithelial cells from milk donated by 40 lactating women. For investigations based on in situ PCR we used 27 unselected archival formalin fixed breast cancer specimens and 18 unselected archival formalin fixed normal breast specimens from women who had breast reduction surgery. Thirteen of these fixed breast cancer specimens were ductal carcinoma in situ (dcis) and 14 were predominantly invasive ductal carcinomas (idc).

Results

EBV sequences were identified in 68%, high risk HPV sequences in 50%, and MMTV sequences in 78% of DNA extracted from 50 invasive breast cancer specimens. These same viruses were identified in selected normal and breast cancer specimens by in situ PCR. Sequences from more than one viral type were identified in 72% of the same breast cancer specimens. Normal controls showed these viruses were also present in epithelial cells in human milk – EBV (35%), HPV, 20%) and MMTV (32%) of 40 milk samples from normal lactating women, with multiple viruses being identified in 13% of the same milk samples.

Conclusions

We conclude that (i) EBV, HPV and MMTV gene sequences are present and co-exist in many human breast cancers, (ii) the presence of these viruses in breast cancer is associated with young age of diagnosis and possibly an increased grade of breast cancer.     

ADH IB Expression,but Not ADH III,Is Decreased in Human Lung Cancer

Endogenous S-nitrosothiols, including S-nitrosoglutathione (GSNO), mediate nitric oxide (NO)-based signaling, inflammatory responses, and smooth muscle function. Reduced GSNO levels have been implicated in several respiratory diseases, and inhibition of GSNO reductase, (GSNOR) the primary enzyme that metabolizes GSNO, represents a novel approach to treating inflammatory lung diseases. Recently, an association between decreased GSNOR expression and human lung cancer risk was proposed in part based on immunohistochemical staining using a polyclonal GSNOR antibody. GSNOR is an isozyme of the alcohol dehydrogenase (ADH) family, and we demonstrate that the antibody used in those studies cross reacts substantially with other ADH proteins and may not be an appropriate reagent. We evaluated human lung cancer tissue arrays using monoclonal antibodies highly specific for human GSNOR with minimal cross reactivity to other ADH proteins. We verified the presence of GSNOR in ≥85% of specimens examined, and extensive analysis of these samples demonstrated no difference in GSNOR protein expression between cancerous and normal lung tissues. Additionally, GSNOR and other ADH mRNA levels were evaluated quantitatively in lung cancer cDNA arrays by qPCR. Consistent with our immunohistochemical findings, GSNOR mRNA levels were not changed in lung cancer tissues, however the expression levels of other ADH genes were decreased. ADH IB mRNA levels were reduced (>10-fold) in 65% of the lung cancer cDNA specimens. We conclude that the previously reported results showed an incorrect association of GSNOR and human lung cancer risk, and a decrease in ADH IB, rather than GSNOR, correlates with human lung cancer.     

Indole-3-Carbinol,a Phytochemical Aryl Hydrocarbon Receptor-Ligand,Induces the mRNA Overexpression of UBE2L3 and Cell Proliferation Arrest

Cervical cancer (CC) is one of the most common cancers in women, and is linked to human papillomavirus (HPV) infection. The virus oncoprotein E6 binds to p53, resulting in its degradation and allowing uncontrolled cell proliferation. Meanwhile, the HPV E7 protein maintains host cell differentiation by targeting retinoblastoma tumor suppressor. The host cell can ubiquitinate E6 and E7 through UBE2L3, whose expression depends on the interaction between the aryl hydrocarbon receptor (AhR) with Xenobiotic Responsive Elements (XREs) located in the UBE2L3 gene promoter. In this study, we used cell culture to determine the effect of indole-3-carbinol (I3C) over cellular viability, apoptosis, cell proliferation, and mRNA levels of UBE2L3 and CYP1A1. In addition, patients’ samples were used to determine the mRNA levels of UBE2L3 and CYP1A1 genes. We found that I3C promotes the activation of AhR and decreases cell proliferation, possibly through UBE2L3 mRNA induction, which would result in the ubiquitination of HPV E7. Since there is a strong requirement for selective and cost-effective cancer treatments, natural AhR ligands such as I3C could represent a novel strategy for cancer treatment.     

Experimental aspects of NPY-decorated gold nanoclusters using randomized hybrid design against breast cancer cell line

Gold nanoclusters (AuNCs) are potential carrier system for bioactive like proteins and peptides used in various therapeutics against various ailments. Neuropeptide Y (NPY) is consists of 36 amino acids used to treat depression, obesity, epilepsy, and so on. but possess instability at higher temperatures causing its limited usage. The present study focused on the NPY-decorated AuNCs prepared using desolvation reduction technique and optimized through randomized hybrid design. ATR-FTIR, ¹H NMR and CD spectroscopic studies confirmed the AuNCs structure interaction with NPY. The optimized NPY-decorated AuNCs possessed 85.6 ± 2.08% of entrapment efficiency with 85.32 ± 7.55% of NPY release for 24 h. It displayed dose-dependent cell cytotoxicity, IC₅₀ value of 0.7 ± 0.05 μg mL^-1 and apoptosis of 68.48 ± 7.35% with controlled cell migration causing G0G1 cell arrest by penetrating cancer cell membrane on MCF-7 cell line. Furthermore, the AuNCs caused surface disruption of the cancerous cell further interrupting the protein synthesis by MAPK pathway leading to cell death. The AuNCs were stable for 3 months at 25 ± 2°C due to steric hindrance. Hence, NPY-decorated AuNCs were found to be effective on MCF-7 cell line with a significant anti-apoptotic effect, further emerging as a novel therapeutic delivery system in the management of breast cancer.     

凋亡抑制基因livin与survivin在乳腺癌中的表达差异

目的探讨凋亡抑制基因livin在乳腺癌发生、发展中的作用及其与survivin基因的表达和乳腺癌生物学行为之间的关系。方法采用逆转录聚合酶链反应(RT-PCR)检测44例乳腺癌组织、40例癌旁正常组织及4个乳腺癌细胞系中livinmRNA和survivin mRNA的表达,并用免疫组化(IHC)EnVision法检测上述组织和细胞中livin和survivin蛋白的表达。结果livin mRNA和survivin mRNA在乳腺癌组织中的阳性表达率分别为72.7%(32/44)和61.4%(27/44),在癌旁正常组织中的阳性率分别为7.50%(3/40)和5.00%(2/40),二者在癌组织中的表达均显著高于在正常组织中的表达(P<0.01)。livin和survivin蛋白表达情况与mRNA结果相似(P<0.01)。livin和survivin在乳腺癌组织中的表达无显著相关性(P>0.05)。4个乳腺癌细胞系中均有survivin mRNA和蛋白的表达,而MCF-7及MDA-MB-435细胞系中呈阴性表达。survivin基因在伴有淋巴结转移的乳腺癌组织中的表达明显高于无淋巴结转移的乳腺癌组织(P=0.0047),livin在雌激素受体(ER)阴性或者Her2/neu阳性表达的乳腺癌中的阳性率有升高的趋势,但并无显著性差异(P>0.05)。结论livin和survivin基因在人乳腺癌组织中表达上调,提示其可能在乳腺癌发生、发展中起重要促进作用,sur-vivin和淋巴结转移的密切关系表明它的高表达可能反映患者较差的预后。livin和survivin基因一样可能成为乳腺癌治疗中的一个靶基因。     

Co-delivery with nano-quercetin enhances doxorubicin-mediated cytotoxicity against MCF-7 cells

Quercetin, the plant-derived phenolic compounds, plays a pivotal role in controlling hemostasis, by having potent antioxidant and free-radical scavenging properties. This flavonoid in combination with chemotherapeutic drugs improves the efficacy of these agents in induction of apoptosis in cancer cells. This study investigated the role of nano-quercetin (phytosome) in doxorubicin-induced apoptosis. Nanoparticles were characterized for particle size, zeta potential, scanning electron microscopy (SEM) and differential scanning calorimetric assessments. Anti-proliferative effect of formulations was evaluated by MTT assay. mRNA expression levels of target genes were measured by real time RT-PCR. The mean size of nanoparticles was 85 ± 2 nm with nearly narrow size distribution which was confirmed by SEM analysis. Our results showed that co-treatment of MCF-7 breast cancer cells with nano-quercetin and doxorubicin increased the percentage of apoptosis from 40.11 ± 7.72–58 ± 7.13 (p < 0.05). Furthermore, mRNA expression levels for downstream genes including NQO1 and MRP1 showed a marked decrease (p < 0.05). Taken together, our results suggest that phytosome technology can elevate the efficacy of chemotherapeutics by increasing the permeability of tumor cells to chemical agents. Our findings introduce a novel phytosome-dependent strategy to improve delivery of doxorubicin to the breast cancerous tissues.     

Ubiquitin-Conjugating Enzyme UBE2C Is Highly Expressed in Breast Microcalcification Lesions

Ubiquitin-conjugating enzyme 2C (UBE2C) contributes to ubiquitin-mediated proteasome degradation of cell cycle progression in breast cancer. Microcalcification (MC) is the most common mammographic feature of early breast cancer. In this study, we evaluated whether UBE2C could be a tumor marker of early breast cancer with MC found on screening mammography. UBE2C protein and mRNA expression were measured in breast core biopsy pairs of MC and adjacent non-MC breast tissue from each subject. Immunohistochemistry revealed UBE2C positivity in 69.4% of MC samples and 77.6% negativity in non-MC samples (p<0.0001). On RT-qPCR, 56.1% of malignant MC lesion samples showed high mRNA level of UBE2C and 80% of benign MC lesion samples showed a low level of UBE2C (p = 0.1766). We investigated the carcinogenic role of UBE2C in MCF-7 breast cancer cells with UBE2C knockdown; UBE2C knockdown downregulated cell proliferation and activated the cellular apoptosis pathway to inhibit cell colony formation. Furthermore, UBE2C expression was associated with that of carcinogenic genes human epidermal growth factor receptor type 2 (HER2), cellular c-Ki-ras2 proto-oncogene (KRAS), vascular endothelial growth factor (VEGF), CXC chemokine receptor 4 (CXCR4), C-C motif chemokine 5 (CCL5), neural precursor cell expressed, developmentally downregulated 9 (NEDD9) and Ras homolog family member C (RhoC). UBE2C may be a marker for diagnosis of nonpalpable breast lesions but not benign or malignant tumors in mammography core biopsies. Suppression of UBE2C may be a potential therapy target in breast cancer.     

Abnormal expression of NRF-2α in hepatocellular carcinoma identified with a newly prepared monoclonal antibody against human NRF-2α protein

Human nuclear respiratory factor 2 alpha subunit (NRF-2α) is fundamentally important to cell function and the development. We aimed to establish the monoclonal antibody (MAb) against the human NRF-2α protein and to investigate its distribution in human hepatocellular carcinoma (HCC) and tumor-adjacent tissues. The 6× His-NRF-2α fusion protein was successfully induced and purified. One monoclonal antibody (MAb) against human NRF-2α, 1-D10-E1-B11-G3 (IgG1), effective in detecting the recombinant and the cellular protein, was characterized. Using immunohistochemical analysis, the expression of NRF-2α was investigated in 38 cases of HCC specimens and 14 cases of tumor-adjacent specimens. Staining was found positive in 9 cases of HCC tissues (23.7%) and 8 cases of normal hepatic tissues (57.1%). The higher-grade frequency of expression of NRF-2α in tumor-adjacent tissues was significantly higher (P < 0.01) than that in tumor tissues, suggesting that NRF-2α may play important roles in carcinogenesis of HCC.