Publications by authors named "Penggao Yang"

6 Publications

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Upregulation of Nogo-B by hypoxia inducible factor-1 and activator protein-1 in hepatocellular carcinoma.

Cancer Sci 2021 May 8. Epub 2021 May 8.

Department of Clinical Laboratory, Shanghai Children's Hospital, Shanghai Jiaotong University, Shanghai, China.

Nogo-B is an important regulator of tumor angiogenesis. Expression of Nogo-B is remarkably upregulated in multiple tumor types, especially hepatocellular carcinoma (HCC). Here, we show the transcriptional regulation mechanisms of Nogo-B in liver cancer. In response to hypoxia, expression of Nogo-B significantly increased in HCC tissues and cells. The distal hypoxia-responsive element in the promoter was essential for transcriptional activation of Nogo-B under hypoxic conditions, which is the specific site for hypoxia inducible factor-1α (HIF-1α) binding. In addition, Nogo-B expression was associated with c-Fos expression in HCC tissues. Nogo-B expression was induced by c-Fos, yet inhibited by a dominant negative mutant A-Fos. Deletion and mutation analysis of the predicted activator protein-1 binding sites revealed that functional element mediated the induction of Nogo-B promoter activity, which was confirmed by ChIP. These results indicate that HIF-1α and c-Fos induce the expression of Nogo-B depending on tumor microenvironments, such as hypoxia and low levels of nutrients, and play a role in upregulation of Nogo-B in tumor angiogenesis.
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http://dx.doi.org/10.1111/cas.14941DOI Listing
May 2021

Beta-catenin can induce hair follicle stem cell differentiation into transit-amplifying cells through c-myc activation.

Tissue Cell 2017 Feb 21;49(1):28-34. Epub 2016 Dec 21.

Department of Burns and Plastic Surgery, Shanghai Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai 201999, China. Electronic address:

Hair follicle stem cells play important roles in maintaining homeostasis and skin tissue self-renewal. Transit-amplifying cells represent the transition of cells from hair follicle stem cells into differentiated epidermal cells. Thus far, the signaling pathway and the molecular biological mechanism that regulate the proliferation and differentiation of hair follicle stem cells remain unclear. In this paper, we studied the relationship between β-catenin and c-myc during the process of the differentiation of hair follicle stem cells into transit-amplifying cells. Based on our results, the expression of β-catenin can activate the nuclear gene c-myc and regulate the expression of transit-amplifying cell markers K15, K19, a6-integrin and β1-integrin, indicating that β-catenin is involved in the transformation process from hair follicle stem cells to transit-amplifying cells and suggesting that β-catenin plays an important biological role in the induction of this differentiation process.
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http://dx.doi.org/10.1016/j.tice.2016.12.005DOI Listing
February 2017

460nm visible light irradiation eradicates MRSA via inducing prophage activation.

J Photochem Photobiol B 2017 Jan 18;166:311-322. Epub 2016 Dec 18.

Department of Burns and Plastic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201999, China; Institute of Traumatic Medicine, School of Medicine, Shanghai Jiao Tong University, Shanghai 201999, China. Electronic address:

A growing number of researches demonstrate that light with a wavelength between 400 and 500nm, namely blue light (BL), has exhibited antibacterial effects on methicillin-resistant Staphylococcus aureus (MRSA) and other microbes. However, there is insufficient evidence to show that BL kills MRSA inside biofilm and the mechanisms underlying the antibacterial effects remain unclear. Here we demonstrate that BL irradiation with 460nm effectively eliminated both planktonic and biofilm MRSA in a dose-dependent manner by utilizing a planktonic MRSA or MRSA biofilm model. Furthermore, using a animal model of skin wound infections with MRSA, we found that 460nm BL showed a therapeutic effect on MRSA infected wounds in mice with significant killing of MRSA, better survival and wound healing. Moreover, RNA sequencing was used to analyze differential gene expressions in MRSA genome after BL irradiation. Our data showed that about one third of up-regulated genes were phage-related. Using phage inhibitor GS-11P, increased prophage activation in MRSA cells induced by BL irradiation was blocked and phage particles were observed. The results indicate that blue visible light irradiation with 460nm is a novel tool for eliminating both planktonic and biofilm MRSA. Prophage activation may be involved in the process. This study may provide a new perspective to understand the antibacterial mechanism by BL.
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http://dx.doi.org/10.1016/j.jphotobiol.2016.12.001DOI Listing
January 2017

[Advances in the research on bactericidal effect of blue light and its mechanism].

Zhonghua Shao Shang Za Zhi 2014 Jun;30(3):258-61

Department of Burns and Plastic Surgery, the Third People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 201900, China. Email:

Blue light is commonly used to kill Propionibacterium acnes in clinic. Furthermore, blue light exhibits a good bactericidal effect against Helicobacter pylori, methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, and many oral bacteria in laboratory studies. The bactericidal mechanism of blue light as commonly accepted consists photo-excitation of intracellular porphyrins resulting in production of cytotoxic reactive oxygen species which can inactivate bacteria. Blue light can kill bacteria without additional exogenous photosensitizers. In addition, it produces little harm to mammalian cells. Therefore, as the increasing emergence of antibiotic resistant microorganisms, blue light might be a good antibacterial tool.
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June 2014

Light-activated sutureless closure of wounds in thin skin.

Lasers Surg Med 2012 Feb 13;44(2):163-7. Epub 2011 Dec 13.

Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA.

Background And Objectives: Closing lacerations in thin eyelid and periorbital skin is time consuming and requires high skill for optimal results. In this study we evaluate the outcomes after single layer closure of wounds in thin skin with a sutureless, light-activated photochemical technique called PTB.

Study Design/materials And Methods: Dorsal skin of the SKH-1 hairless mouse was used as a model for eyelid skin. Incisions (1.2 cm) were treated with 0.1% Rose Bengal dye followed by exposure to 532 nm radiation (25, 50, or 100 J/cm(2); 0.25 W/cm(2)) for PTB. Other incisions were sutured (five 10-0 monofilament), exposed only to 532 nm (100 J/cm(2)), or not treated. Outcomes were immediate seal strength (pressure causing leakage through incision of saline infused under wound), skin strength at 1, 3, and 7 days (measured by tensiometry), inflammatory infiltrate at 1, 3, and 7 days (histological assessment), and procedure time.

Results: The immediate seal strength, as measured by leak pressure, was equivalent for all PTB fluences and for sutures (27-32 mmHg); these pressures were significantly greater than for the controls (untreated incisions or laser only treatment; P < 0.001). The ultimate strength of PTB-sealed incisions was greater than the controls at day 1 (P < 0.05) and day 3 (P < 0.025) and all groups were equivalent at day 7. Sutures produced greater inflammatory infiltrate at day 1 than observed in other groups (P = 0.019). The average procedure time for sutured closure (311 seconds) was longer than for the PTB group treated with 25 J/cm(2) (160 seconds) but shorter than the group treated with 100 J/cm(2) (460 seconds).

Conclusion: PTB produces an immediate seal of incisions in thin, delicate skin that heals well, is more rapid than suturing, does not require painful suture removal and is easy to apply.
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http://dx.doi.org/10.1002/lsm.21137DOI Listing
February 2012

Light-initiated bonding of amniotic membrane to cornea.

Invest Ophthalmol Vis Sci 2011 Dec 9;52(13):9470-7. Epub 2011 Dec 9.

Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA.

Purpose: Suturing amniotic membrane to cornea during surgery is time consuming, and sutures may further damage the eye. The authors introduce a novel sutureless, light-activated technique that securely attaches amnion to cornea through protein-protein crosslinks.

Methods: Cryopreserved human amniotic membrane, stained with Rose Bengal (RB), was placed over a full-thickness wound in deepithelialized rabbit cornea and was treated with green laser. The intraocular pressure that broke the seal (IOP(L)) was measured, and adhesion was measured with a peel test. The influences on bonding strength of fluence, irradiance, RB concentration, and amnion surface bonded were measured. Epithelial cell migration on treated amnion and keratocyte viability after bonding were also measured. The involvement in the bonding mechanism of oxygen, singlet oxygen, and association of RB with stromal collagen was investigated.

Results: Sealing amniotic membrane over cornea using 0.1% RB and 150 J/cm(2) at 532 nm produced an IOP(L) of 261 ± 77 mm Hg ex vivo and 448 mm ± 212 mm Hg in vivo. The ex vivo IOP(L) increased with increasing fluence (50-150 J/cm(2)). Equivalent IOP(L) was produced for bonding basement membrane or stromal amnion surfaces. The bonding treatment was not toxic to keratocytes but slightly reduced the migration of corneal epithelial cells on amnion ex vivo. Mechanism studies indicated that RB forms two complexes with amnion stromal collagen, that bonding requires oxygen, and that singlet oxygen mediates protein crosslinking.

Conclusions: A rapid, light-activated technique produces strong, immediate bonding between amnion and cornea and merits further evaluation for ocular surface surgeries.
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http://dx.doi.org/10.1167/iovs.11-7248DOI Listing
December 2011