Role-Shifting PKCζ Fosters Its Own Proapoptotic Destruction by Complexing with Bcl10 at the Nuclear Envelope of Human Cervical Carcinoma Cells: A Proteomic and Biochemical Study

AC010883.5 promotes cell proliferation, invasion, migration, and epithelial-to-mesenchymal transition in cervical cancer by modulating the MAPK signaling pathway

Homo sapiens chromosome 2 clone RP11-339H12 (AC010883.5) is a dysregulated long non-coding RNA (lncRNA) that has never been investigated in cervical cancer (CC). Thus, the potential function and molecular mechanism remain unclear. Our study explored the biological function of AC010883.5 to determine the underlying mechanisms in CC and provide potential therapeutic targets for improving the clinical treatment strategy. We used quantitative real-time polymerase chain reaction to measure mitochondrial RNA levels and western blot to measure the protein levels of target genes. Further, we used Cell Counting Kit-8 and 5-Bromo-2'-deoxyuridine incorporation assays to evaluate cell proliferation in vitro. Cell apoptosis was analyzed by flow cytometry. Cell invasion was analyzed by wound healing and Transwell migration assays was ued to analyze cell migration. Finally, the biological function and mechanism of AC010883.5 in CC growth were evaluated by in vivo xenograft assay. AC010883.5 was enhanced in CC tissues and cell lines, and enhanced AC010883.5 expression accelerated CC cell proliferation, migration, and invasion and induced epithelial-mesenchymal transition in vitro and in vivo. AC010883.5 also activated the mitogen-activated protein kinase (MAPK) signaling pathway by promoting phosphorylation of extracellular signal-regulated kinase 1/2 (i.e., ERK1/2) and MAPK kinase 1/2 (i.e., MEK1/2). Blocking the MAPK signaling pathway could counteract the pro-proliferative, pro-migrative, and pro-invasive effects of AC010883.5 over-expression. We found that the lncRNA, AC010883.5, is an oncogenic molecule involved in CC tumor progression via dysregulation of the MAPK signaling pathway, implying that AC010883.5 could be a tumor progression and therapeutic response biomarker.

Over Expressed TKTL1, CIP-2A, and B-MYB Proteins in Uterine Cervix Epithelium Scrapings as Potential Risk Predictive Biomarkers in HR-HPV-Infected LSIL/ASCUS Patients

High oncogenic risk human papillomaviruses (HR-HPVs) promote cervical carcinoma development, the fourth most common feminine cancer. A slow oncodevelopmental phase—defined histopathologically as Cervical Intraepithelial Neoplasia (CIN) grades 1–3, or cytologically as Low- or High-grade Squamous Intraepithelial Lesions (LSIL or HSIL)—precedes the malignancy. Cervical carcinoma screenings through HR-HPV genotyping and Pap smears are regularly performed in Western countries. Faulty cytology screening or genotyping or patients' non-compliance with follow-ups can let slip an oncoprogression diagnosis. Novel biomarker tests flanking HR-HPV genotyping and cytology could objectively predict the risk of disease progression thus helping triage LSIL/ASCUS patients. Here, anonymized leftovers of fresh cervical epithelium scrapings from twice (LSIL/ASCUS and HR-HPV DNA)-positive and twice (Pap smear- and HR-HPV DNA)-negative (control) patients in a proteome-preserving solution served to assess the biomarker worth of three cervical carcinoma-related proteins, i.e., B-MYB (or MYBL2), Cancerous Inhibitor of PP2A (CIP-2a), and transketolase-like1 (TKTL1). Leftovers anonymity was strictly kept and storage at −80°C, protein extraction, immunoblotting, and band densitometry were blindly performed. Only after tests completion, the anonymous yet code-corresponding HR-HPV-genotyping and cytology data allowed to assign each sample to the twice-positive or twice-negative group. Descriptive statistics showed that the three proteins levels significantly increased in the twice-positive vs. twice-negative scrapings. Diagnostic ROC curve analysis identified each protein's Optimal Decision Threshold (OTD) showing that TKTL1 and CIP-2a are stronger risk predictive biomarkers (Sensitivity, 0.91–0.93; Specificity, 0.77–0.83) than B-MYB. Logistic Regression coupled with Likelihood-Ratio Tests confirmed that a highly significant relation links increasing TKTL1/CIP-2a/B-MYB protein levels in twice-positive cervical scrapings to the risk of HR-HPV-driven oncoprogression. Finally, a 3 year clinical follow-up showed that 13 patients (50% of total) of the twice-positive group with biomarker values over OTDs compliantly underwent scheduled colposcopy and biopsy. Of these, 11 (i.e., 84.7%) received a positive histological diagnosis, i.e., CIN1 (n = 5; 38.5%) or CIN2/CIN2+ (n = 6; 46,2%). Therefore, TKTL1/CIP-2a/B-MYB protein levels could objectively predict oncoprogression risk in twice (HR-HPV- and Pap smear)-positive women. Further studies will assess the translatability of these findings into clinical settings.

Studies on sporadic non-syndromic thoracic aortic aneurysms: 1. Deregulation of Jagged/Notch 1 homeostasis and selection of synthetic/secretor phenotype smooth muscle cells

Background

Sporadic non-syndromic thoracic aortic aneurysms (SNSTAAs) are less well understood than familial non-syndromic or syndromic ones. The study aimed at defining the peculiar morphologic and molecular changes occurring in the media layer of SNSTAAs.

Design

This study was based on a single centre design.

Methods

Media layer samples taken from seven carefully selected SNSTAAs and seven reference patients (controls) were investigated via quantitative polymerase chain reaction, proteomics-bioinformatics, immunoblotting, quantitative histology, and immunohistochemistry/immunofluorescence.

Results

In SNSTAAs media, aortic smooth muscle cells numbers were halved due to an apoptotic process coupled with a negligible cell proliferation. Cystathionine γ-lyase was diffusely up-regulated. Surviving aortic smooth muscle cells exhibited diverging phenotypes: in inner- and outer-media contractile cells prevailed, having higher contents of smooth-muscle-α-actin holoprotein (45-kDa) and of caspase-3-cleaved smooth-muscle-α-actin 25-kDa fragments; in mid-media, aortic smooth muscle cells exhibited a synthetic/secretor phenotype, down-regulating vimentin, but up-regulating glial fibrillary acidic protein, trans-Golgi network 46 protein, Jagged1 (172-kDa) holoprotein, and Jagged1’s receptor Notch1. Extracellular soluble Jagged1 (42-kDa) fragments accumulated.

Conclusions

In SNSTAAs, there is a relentless aortic smooth muscle cells attrition caused by the up-regulated cystathionine γ-lyase. In mid-media, synthetic/secretor aortic smooth muscle cells intensify Jagged1/NOTCH1 signalling in the attempt to counterbalance the weakened aortic wall, due to aortic smooth muscle cells net loss and mechanical stress. Synthetic/secretor aortic smooth muscle cells are apoptosis-prone, and the accruing thrombin-cleaved Jagged1 fragments counteract the otherwise useful effects of Jagged1/NOTCH1 signalling, thus hampering tissue homeostasis/remodelling, and aortic smooth muscle cells adhesion, differentiation, and migration.

Biocompatible Silk Noil-Based Three-Dimensional Carded-Needled Nonwoven Scaffolds Guide the Engineering of Novel Skin Connective Tissue

Retracting hypertrophic scars resulting from healed burn wounds heavily impact on the patients' life quality. Biomaterial scaffolds guiding burned-out skin regeneration could suppress or lessen scar retraction. Here we report a novel silk noil-based three-dimensional (3D) nonwoven scaffold produced by carding and needling with no formic acid exposure, which might improve burn healing. Once wetted, it displays human skin-like physical features and a high biocompatibility. Human keratinocyte-like cervical carcinoma C4-I cells seeded onto the carded-needled nonwovens in vitro quickly adhered to them, grew, and actively metabolized glutamine releasing lactate. As on plastic, they released no proinflammatory IL-1β, although secreting tumor necrosis factor-alpha, an inducer of the autocrine mitogen amphiregulin in such cells. Once grafted into interscapular subcutaneous tissue of mice, carded-needled nonwovens guided the afresh assembly of a connective tissue enveloping the fibroin microfibers and filling the interposed voids within 3 months. Fibroblasts and a few poly- or mononucleated macrophages populated the engineered tissue. Besides, its extracellular matrix contained thin sparse collagen fibrils and a newly formed vascular network whose endothelin-1-expressing endothelial cells grew first on the fibroin microfibrils and later expanded into the intervening matrix. Remarkably, no infiltrates of inflammatory leukocytes and no packed collagen fibers bundles among fibroin microfibers, no fibrous capsules at the grafts periphery, and hence no foreign body response was obtained at the end of 3 months of observation. Therefore, we posit that silk noil-based 3D carded-needled nonwoven scaffolds are tools for translational medicine studies as they could guide connective tissue regeneration at deep burn wounds averting scar retraction with good functional results.

Bcl10 crucially nucleates the pro-apoptotic complexes comprising PDK1, PKCζ and caspase-3 at the nuclear envelope of etoposide-treated human cervical carcinoma C4-I cells

Protein kinase (PK)Cζ signaling at various subcellular levels affects cell survival, differentiation, growth and/or apoptosis. However, the mechanisms modulating PKCζ activity at the nuclear membrane (NM) are not yet fully understood. Previously, we demonstrated that PKCζ interacts with the B‑cell lymphoma 10 (Bcl10) protein at the NM of human cervical carcinoma (HCC) C4‑I cells. In the present study, we aimed to further clarify the interactions between PKCζ, Bcl10 and other proteins co-immunoprecipitated from NMs isolated from untreated and etoposide (also known as VP‑16; 2.0 µg/ml)‑treated C4‑I cells using biochemical and proteomics analyses. Aside from the Bcl10 protein, 3‑phosphoinositide‑dependent protein kinase‑1 (PDK1) also co-immunoprecipitated with PKCζ from NMs of C4‑I cells, indicating the assembly of a heterotrimeric complex, which increased with time in VP‑16‑exposed cells, as did the activity of PDK1‑phosphorylated‑PKCζ. In turn, PKCζ‑phosphorylated‑Bcl10 straddled an enlarged complex which comprised caspase‑3. Subsequently, activity‑enhanced caspase‑3 cleaved and inactivated PKCζ. Finally, the suppression of Bcl10 using specific siRNA or lentiviral transduction prevented the increase in the PDK1•PKCζ association, the increase in the activity of PKCζ and caspase‑3, as well as the caspase‑3‑mediated PKCζ proteolysis and inactivation from occurring at the NMs of the VP‑16‑exposed C4‑I cells. Our observations provide evidence that Bcl10 acts as a pivotal pro-apoptotic protein which crucially nucleates complexes comprising PDK1, PKCζ and active caspase‑3 at the NMs of VP‑16‑exposed C4‑I cells. Hence, our data suggest that Bcl10 and PKCζ are potential therapeutic targets in the treatment of HCC.