IU Indianapolis ScholarWorks :: Browsing by Author "Xie, Jingwu"

Browsing by Author "Xie, Jingwu"

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Aberrant cholesterol metabolism in colorectal cancer represents a targetable vulnerability
(Elsevier, 2023-07) Xie, Jingwu; Nguyen, Chi Mai; Turk, Anita; Nan, Hongmei; Imperiale, Thomas F.; House, Michael; Huang, Kun; Su, Jing; Biostatistics, School of Public Health
Activation of hedgehog signaling is not a frequent event in ovarian cancers
(BioMed Central, 2009-11-27) Yang, Ling; He, Jing; Huang, Shuhong; Zhang, Xiaoli; Bian, Yuehong; He, Nonggao; Zhang, Hongwei; Xie, Jingwu; Pediatrics, School of Medicine
The hedgehog (Hh) signaling pathway regulates many processes of development and tissue homeostasis. Activation of hedgehog signaling has been reported in about 30% of human cancer including ovarian cancer. Inhibition of hedgehog signaling has been pursued as an effective strategy for cancer treatment including an ongoing phase II clinical trial in ovarian cancer. However, the rate of hedgehog signaling activation in ovarian cancer was reported differently by different groups. To predict the successful for future clinical trials of hedgehog signaling inhibitors in ovarian cancer, we assessed hedgehog pathway activation in 34 ovarian epithelial tumor specimens through analyses of target gene expression by in-situ hybridization, immunohistochemistry, RT-PCR and real-time PCR. In contrast to previous reports, we only detected a small proportion of ovarian cancers with hedgehog target gene expression, suggesting that identification of the tumors with activated hedgehog signaling activation will facilitate chemotherapy with hedgehog signaling inhibitors.
Activation of the Hedgehog signaling pathway leads to fibrosis in aortic valves
(BMC, 2023-03-02) Gu, Dongsheng; Soepriatna, Arvin H.; Zhang, Wenjun; Li, Jun; Zhao, Jenny; Zhang, Xiaoli; Shu, Xianhong; Wang, Yongshi; Landis, Benjamin J.; Goergen, Craig J.; Xie, Jingwu; Pediatrics, School of Medicine
Background: Fibrosis is a pathological wound healing process characterized by excessive extracellular matrix deposition, which interferes with normal organ function and contributes to ~ 45% of human mortality. Fibrosis develops in response to chronic injury in nearly all organs, but the a cascade of events leading to fibrosis remains unclear. While hedgehog (Hh) signaling activation has been associated with fibrosis in the lung, kidney, and skin, it is unknown whether hedgehog signaling activation is the cause or the consequence of fibrosis. We hypothesize that activation of hedgehog signaling is sufficient to drive fibrosis in mouse models. Results: In this study, we provide direct evidence to show that activation of Hh signaling via expression of activated smoothened, SmoM2, is sufficient to induce fibrosis in the vasculature and aortic valves. We showed that activated SmoM2 -induced fibrosis is associated with abnormal function of aortic valves and heart. The relevance of this mouse model to human health is reflected in our findings that elevated GLI expression is detected in 6 out of 11 aortic valves from patients with fibrotic aortic valves. Conclusions: Our data show that activating hedgehog signaling is sufficient to drive fibrosis in mice, and this mouse model is relevant to human aortic valve stenosis.
Combining hedgehog signaling inhibition with focal irradiation on reduction of pancreatic cancer metastasis
(American Association for Cancer Research, 2013) Gu, Dongsheng; Liu, Hailan; Su, Gloria H.; Zhang, Xiaoli; Chin-Sinex, Helen; Hanenberg, Helmut; Mendonca, Marc S.; Shannon, Harlan E.; Chiorean, E. Gabriela; Xie, Jingwu; Pediatrics, School of Medicine
Pancreatic cancer often presents in advanced stages and is unresponsive to conventional treatments. Thus, the need to develop novel treatment strategies for pancreatic cancer has never been greater. Here, we report that combination of focal irradiation with hedgehog (Hh) signaling inhibition exerts better than additive effects on reducing metastases. In an orthotopic model, we found that focal irradiation alone effectively reduced primary tumor growth but did not significantly affect metastasis. We hypothesized that cancer stem cells (CSC) of pancreatic cancer are responsible for the residual tumors following irradiation, which may be regulated by Hh signaling. To test our hypothesis, we showed that tumor metastasis in our model was accompanied by increased expression of CSC cell surface markers as well as Hh target genes. We generated tumor spheres from orthotopic pancreatic and metastatic tumors, which have elevated levels of CSC markers relative to the parental cells and elevated expression of Hh target genes. Irradiation of tumor spheres further elevated CSC cell surface markers and increased Hh target gene expression. Combination of Hh signaling inhibition with radiation had more than additive effects on tumor sphere regeneration in vitro. This phenotype was observed in two independent cell lines. In our orthotopic animal model, focal radiation plus Hh inhibition had more than additive effects on reducing lymph node metastasis. We identified several potential molecules in mediating Hh signaling effects. Taken together, our data provide a rationale for combined use of Hh inhibition with irradiation for clinical treatment of patients with pancreatic cancer.
A critical role of AREG for bleomycin-induced skin fibrosis
(BMC, 2021) Zhang, Mary Yinghua; Fang, Shuyi; Gao, Hongyu; Zhang, Xiaoli; Gu, Dongsheng; Liu, Yunlong; Wan, Jun; Xie, Jingwu; Pediatrics, School of Medicine
We report our discovery of an important player in the development of skin fibrosis, a hallmark of scleroderma. Scleroderma is a fibrotic disease, affecting 70,000 to 150,000 Americans. Fibrosis is a pathological wound healing process that produces an excessive extracellular matrix to interfere with normal organ function. Fibrosis contributes to nearly half of human mortality. Scleroderma has heterogeneous phenotypes, unpredictable outcomes, no validated biomarkers, and no effective treatment. Thus, strategies to slow down scleroderma progression represent an urgent medical need. While a pathological wound healing process like fibrosis leaves scars and weakens organ function, oral mucosa wound healing is a scarless process. After re-analyses of gene expression datasets from oral mucosa wound healing and skin fibrosis, we discovered that several pathways constitutively activated in skin fibrosis are transiently induced during oral mucosa wound healing process, particularly the amphiregulin (Areg) gene. Areg expression is upregulated ~ 10 folds 24hrs after oral mucosa wound but reduced to the basal level 3 days later. During bleomycin-induced skin fibrosis, a commonly used mouse model for skin fibrosis, Areg is up-regulated throughout the fibrogenesis and is associated with elevated cell proliferation in the dermis. To demonstrate the role of Areg for skin fibrosis, we used mice with Areg knockout, and found that Areg deficiency essentially prevents bleomycin-induced skin fibrosis. We further determined that bleomycin-induced cell proliferation in the dermis was not observed in the Areg null mice. Furthermore, we found that inhibiting MEK, a downstream signaling effector of Areg, by selumetinib also effectively blocked bleomycin-based skin fibrosis model. Based on these results, we concluded that the Areg-EGFR-MEK signaling axis is critical for skin fibrosis development. Blocking this signaling axis may be effective in treating scleroderma.
Deciphering the role of hedgehog signaling in pancreatic cancer.
(JBR, 2016-09) Gu, Dongsheng; Schlotman, Kelly E.; Xie, Jingwu; Department of Pediatrics, IU School of Medicine
Pancreatic cancer, mostly pancreatic ductal adenocarcinoma (PDAC), is a leading cause of cancer-related death in the US, with a dismal median survival of 6 months. Thus, there is an urgent unmet need to identify ways to diagnose and to treat this deadly cancer. Although a number of genetic changes have been identified in pancreatic cancer, their mechanisms of action in tumor development, progression and metastasis are not completely understood. Hedgehog signaling, which plays a major role in embryonic development and stem cell regulation, is known to be activated in pancreatic cancer; however, specific inhibitors targeting the smoothened molecule failed to improve the condition of pancreatic cancer patients in clinical trials. Furthermore, results regarding the role of Hh signaling in pancreatic cancer are controversial with some reporting tumor promoting activities whereas others tumor suppressive actions. In this review, we will summarize what we know about hedgehog signaling in pancreatic cancer, and try to explain the contradicting roles of hedgehog signaling as well as the reason(s) behind the failed clinical trials. In addition to the canonical hedgehog signaling, we will also discuss several non-canonical hedgehog signaling mechanisms.
Defective TGFβ signaling in bone marrow-derived cells prevents Hedgehog-induced skin tumors
(American Association for Cancer Research, 2014-01-15) Fan, Qipeng; Gu, Dongsheng; Liu, Hailan; Yang, Ling; Zhang, Xiaoli; Yoder, Mervin C.; Kaplan, Mark H.; Xie, Jingwu; Department of Pediatrics, IU School of Medicine
Hedgehog (Hh) signaling in cancer cells drives changes in the tumor microenvironment that are incompletely understood. Here we report that Hh- driven tumors exhibit an increase in myeloid-derived suppressor cells (MDSC) and a decrease in T cells, indicative of an immune suppressive tumor microenvironment. This change was associated with activated TGFβ signaling in several cell types in BCCs. We determined that TGFβ signaling in bone marrow (BM)-derived cells, not keratinocytes, regulates MDSC and promotes tumor development. Tgfbr2 deficiency in the BM-derived cells also reduced the size of previously developed tumors in mice. We identified CCL2 as the major chemokine attracting MDSC to tumor, whose expression was Tgfbr2-dependent, whereas its receptor CCR2 was highly expressed in MDSC population. CCL2 alone was sufficient to induce migration of MDSC. Moreover, the CCR2 inhibitors prevented MDSC migration towards skin cells in vitro, reduced MDSC accumulation and Hh signaling-driven tumor development in mice. Our results reveal a signaling network critical for Hh signaling in cancer cells to establish an effective immune suppressive microenvironment during tumor development.
Distinct transcriptomic landscapes of cutaneous basal cell carcinomas and squamous cell carcinomas
(Elsevier, 2019) Wan, Jun; Dai, Hongji; Zhang, Xiaoli; Liu, Sheng; Lin, Yuan; Somani, Ally-Khan; Xie, Jingwu; Han, Jiali; Medical and Molecular Genetics, School of Medicine
The majority of non-melanoma skin cancer (NMSC) is cutaneous basal cell carcinoma (BCC) or squamous cell carcinoma (SCC), which are also called keratinocyte carcinomas, as both of them originate from keratinocytes. The incidence of keratinocyte carcinomas is over 5 million per year in the US, three-fold higher than the total incidence of all other types of cancer combined. While there are several reports on gene expression profiling of BCC and SCC, there are significant variations in the reported gene expression changes in different studies. One reason is that tumor-adjacent normal skin specimens were not included in many studies as matched controls. Furthermore, while numerous studies of skin stem cells in mouse models have been reported, their relevance to human skin cancer remains unknown. In this report, we analyzed gene expression profiles of paired specimens of keratinocyte carcinomas with their matched normal skin tissues as the control. Among several novel findings, we discovered a significant number of zinc finger encoding genes up-regulated in human BCC. In BCC, a novel link was found between hedgehog signaling, Wnt signaling, and the cilium. While the SCC cancer-stem-cell gene signature is shared between human and mouse SCCs, the hair follicle stem-cell signature of mice was not highly represented in human SCC. Differential gene expression (DEG) in human BCC shares gene signature with both bulge and epidermal stem cells. We have also determined that human BCCs and SCCs have distinct gene expression patterns, and some of them are not fully reflected in current mouse models.
Functional significance of Hippo/YAP signaling for drug resistance in colorectal cancer
(Wiley, 2018) Song, Ruolan; Gu, Dongsheng; Zhang, Lining; Zhang, Xiaoli; Yu, Beiqin; Liu, Bingya; Xie, Jingwu; Pediatrics, School of Medicine
Colorectal cancer is a leading cause of cancer‐related death worldwide. While early stage colorectal cancer can be removed by surgery, patients with advanced disease are treated by chemotherapy, with 5‐Fluorouracil (5‐FU) as a main ingredient. However, most patients with advanced colorectal cancer eventually succumb to the disease despite some responded initially. Thus, identifying molecular mechanisms responsible for drug resistance will help design novel strategies to treat colorectal cancer. In this study, we analyzed an acquired 5‐FU resistant cell line, LoVo‐R, and determined that elevated expression of YAP target genes is a major alteration in the 5‐FU resistant cells. Hippo/YAP signaling, a pathway essential for cell polarity, is an important regulator for tissue homeostasis, organ size, and stem cells. We demonstrated that knockdown of YAP1 sensitized LoVo‐R cells to 5‐FU treatment in cultured cells and in mice. The relevance of our studies to colorectal cancer patients is reflected by our discovery that high expression of YAP target genes in the tumor was associated with an increased risk of cancer relapse and poor survival in a larger cohort of colorectal cancer patients who underwent 5‐FU‐related chemotherapy. Taken together, we demonstrate a critical role of YAP signaling for drug resistance in colorectal cancer.
Genetic Evidence for XPC-KRAS Interactions During Lung Cancer Development.
(Elsevier, 2015-10-20) Zhang, Xiaoli; He, Nonggao; Gu, Dongsheng; Wickliffe, Jeff; Salazar, James; Boldogh, Istavan; Xie, Jingwu; Department of Pediatrics, IU School of Medicine
Lung cancer causes more deaths than breast, colorectal and prostate cancers combined. Despite major advances in targeted therapy in a subset of lung adenocarcinomas, the overall 5-year survival rate for lung cancer worldwide has not significantly changed for the last few decades. DNA repair deficiency is known to contribute to lung cancer development. In fact, human polymorphisms in DNA repair genes such as xeroderma pigmentosum group C (XPC) are highly associated with lung cancer incidence. However, the direct genetic evidence for the role of XPC for lung cancer development is still lacking. Mutations of the Kirsten rat sarcoma viral oncogene homolog (Kras) or its downstream effector genes occur in almost all lung cancer cells, and there are a number of mouse models for lung cancer using these mutations. Using activated Kras, KrasLA1, as a driver for lung cancer development in mice, we showed for the first time that mice with KrasLA1 and Xpc knockout had worst outcomes in lung cancer development, and this phenotype was associated with accumulated DNA damage. Using cultured cells, we demonstrated that induced expression of oncogenic KRASG12V led to increased levels of reactive oxygen species (ROS) as well as DNA damage, and both can be suppressed by anti-oxidants. Thus, it appears that XPC may help repair DNA damage caused by KRAS-mediated production of ROS.

Browsing by Author "Xie, Jingwu"

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