Omar Haji Shair

Dr. Omar Haji Shair


Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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28 August 2019 in Molecules
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YJYoung Yun Jung
Young Yun Jung
EZEastern Zhuang
Eastern Zhuang
ACArunachalam Chinnathambi
Arunachalam Chinnathambi
SASulaiman Ail Alharbi
Sulaiman Ail Alharbi
OSOmar Haji Shair
Omar Haji Shair
KAKwang Seok Ahn
Kwang Seok Ahn
Fangchinoline (FCN) derived from Stephaniae tetrandrine S. Moore can be employed to treat fever, inflammation, rheumatism arthralgia, edema, dysuria, athlete’s foot, and swollen wet sores. FCN can exhibit a plethora of anti-neoplastic effects although its precise mode of action still remains to be deciphered. Nuclear factor-κB (NF-κB) and activator protein-1 (AP-1) can closely regulate carcinogenesis and thus we analyzed the possible action of FCN may have on these two signaling cascades in tumor cells. The effect of FCN on NF-κB and AP-1 signaling cascades and its downstream functions was deciphered using diverse assays in both human chronic myeloid leukemia (KBM5) and multiple myeloma (U266). FCN attenuated growth of both leukemic and multiple myeloma cells and repressed NF-κB, and AP-1 activation through diverse mechanisms, including attenuation of phosphorylation of IκB kinase (IKK) and p65. Furthermore, FCN could also cause significant enhancement in TNFα-driven apoptosis as studied by various molecular techniques. Thus, FCN may exhibit potent anti-neoplastic effects by affecting diverse oncogenic pathways and may be employed as pro-apoptotic agent against various malignancies.

Verified
Journal Article
Open access
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HWhong wang
hong wang
KAKwang Seok Ahn
Kwang Seok Ahn
SASulaiman Ail Alharbi
Sulaiman Ail Alharbi
OSOmar Haji Shair
Omar Haji Shair
FAFrank Arfuso
Frank Arfuso
Feng Ru TangFeng Ru Tang
Feng Ru Tang
The present study aimed to explore the possible radioprotective effects of celastrol and relevant molecular mechanisms in an in vitro cell and in vivo mouse models exposed to gamma radiation. Human keratinocytes (HaCaT) and foreskin fibroblast (BJ) cells were exposed to gamma radiation of 20 Gy, followed by treatment with celastrol for 24 h. Cell viability, reactive oxygen species (ROS), nitric oxide (NO) and glutathione (GSH) production, lipid peroxidation, DNA damage, inflammatory cytokine levels, and NF-κB pathway activation were examined. The survival rate, levels of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) in blood, and p65 and phospho-p65 expression were also evaluated in mice after exposure to gamma radiation and celastrol treatment. The gamma irradiation of HaCaT cells induced decreased cell viability, but treatment with celastrol significantly blocked this cytotoxicity. Gamma irradiation also increased free radical production (e.g., ROS and NO), decreased the level of GSH, and enhanced oxidative DNA damage and lipid peroxidation in cells, which were effectively reversed by celastrol treatment. Moreover, inflammatory responses induced by gamma irradiation, as demonstrated by increased levels of IL-6, TNF-α, and IL-1β, were also blocked by celastrol. The increased activity of NF-κB DNA binding following gamma radiation was significantly attenuated after celastrol treatment. In the irradiated mice, treatment with celastrol significantly improved overall survival rate, reduced the excessive inflammatory responses, and decreased NF-κB activity. As a NF-κB pathway blocker and antioxidant, celastrol may represent a promising pharmacological agent with protective effects against gamma irradiation-induced injury.

7 July 2019 in Biomolecules
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CKChulwon Kim
Chulwon Kim
JLJong Hyun Lee
Jong Hyun Lee
JKJeong-Hyeon Ko
Jeong-Hyeon Ko
ACArunachalam Chinnathambi
Arunachalam Chinnathambi
SASulaiman Ail Alharbi
Sulaiman Ail Alharbi
KAKwang Seok Ahn
Kwang Seok Ahn
Here, we determined the anti-neoplastic actions of formononetin (FT) against multiple myeloma (MM) and elucidated its possible mode of action. It was observed that FT enhanced the apoptosis caused by bortezomib (Bor) and mitigated proliferation in MM cells, and these events are regulated by nuclear factor-κB (NF-κB), phosphatidylinositol 3-kinase (PI3K)/AKT, and activator protein-1 (AP-1) activation. We further noted that FT treatment reduced the levels of diverse tumorigenic proteins involved in myeloma progression and survival. Interestingly, we observed that FT also blocked persistent NF-κB, PI3K/AKT, and AP-1 activation in myeloma cells. FT suppressed the activation of these oncogenic cascades by affecting a number of signaling molecules involved in their cellular regulation. In addition, FT augmented tumor growth-inhibitory potential of Bor in MM preclinical mouse model. Thus, FT can be employed with proteasomal inhibitors for myeloma therapy by regulating the activation of diverse oncogenic transcription factors involved in myeloma growth.

7 April 2026 in EuroMediterranean Biomedical Journal
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OSOmar Haji Shair
Omar Haji Shair
RARashead M. Alssum
Rashead M. Alssum
Microorganisms play an extensive role in the decomposition of many organic matters and are in symbiotic relationship with plants and animals. In this study, concentration containing 57 mg/ml malathion was diluted and used to spray soil sample collected from Riyadh area, Saudi Arabia Total chromosomal soil microorganisms were isolated from sprayed and non sprayed samples. Absence and presences of PCR band profiles were assumed to represent the absence or presence of bacteria. A maximum 7mg/ml and minimum 0.2mg/4.16 ul of malathion concentration was used in a nutrient agar medium for bacterial growth. The fingerprinting profiles of treated soil samples demonstrated the missing of some fingerprint bands which were present in the profiles of non treated soil samples. It was concluded that malathion had a misbalancing effect on the soil flora bacteria. However, smearing with maximum malathion concentration in nutrient agar supporting bacterial growth was observed. While a minimum concentration in the same nutrient agar was not supporting.