Hina Mir

CXCR6-CXCL16 axis promotes prostate cancer by mediating cytoskeleton rearrangement via Ezrin activation and α v β 3 integrin clustering

Cytoskeletal rearrangement is required for migration and invasion, which are the key steps of cancer metastasis. Ezrin and integrin co-ordinate these processes by regulating cellular adhesion and cytoskeletal polymerization-depolymerization. It is also well established that chemokine-chemokine receptor axis plays a crucial role in regulating cancer cell migration and invasion. In this study, we show involvement of CXC chemokine receptor 6 (CXCR6) and its only natural ligand CXCL16 in pathobiology of prostate cancer (PCa). CXCR6 is highly expressed in PCa tissues and cell lines (LNCaP and PC3), relative to normal tissue and cells. CXCR6 expression in PCa tissues correlated with higher Gleason score. Similarly, aggressive PCa cells (PC3) show high CXCR6 compared to less aggressive LNCaP. Besides, PC3 cells show higher MMPs expression compared to LNCaP cells following CXCL16 stimulation. Intriguingly, CXCR6-CXCL16 interaction in PCa cells promotes Ezrin activation, αvβ3 integrin clustering and capping at the leading edge in FAK/PI3K/PKC dependent manner, thereby modifying cellular adhesion as well as motility. Together these results demonstrate that CXCL16 stimulation changes cytoskeletal dynamics resulting in enhanced migration, invasion and adhesion to endothelial cells, ultimately enabling PCa cells to achieve their metastatic goal.

Andrographolide inhibits prostate cancer by targeting cell cycle regulators, CXCR3 and CXCR7 chemokine receptors.

ABSTRACT Despite state of the art cancer diagnostics and therapies offered in clinic, prostate cancer (PCa) remains the second leading cause of cancer-related deaths. Hence, more robust therapeutic/preventive regimes are required to combat this lethal disease. In the current study, we have tested the efficacy of Andrographolide (AG), a bioactive diterpenoid isolated from Andrographis paniculata, against PCa. This natural agent selectively affects PCa cell viability in a dose and time-dependent manner, without affecting primary prostate epithelial cells. Furthermore, AG showed differential effect on cell cycle phases in LNCaP, C4-2b and PC3 cells compared to retinoblastoma protein (RB−/−) and CDKN2A lacking DU-145 cells. G2/M transition was blocked in LNCaP, C4-2b and PC3 after AG treatment whereas DU-145 cells failed to transit G1/S phase. This difference was primarily due to differential activation of cell cycle regulators in these cell lines. Levels of cyclin A2 after AG treatment increased in all PCa cells line. Cyclin B1 levels increased in LNCaP and PC3, decreased in C4-2b and showed no difference in DU-145 cells after AG treatment. AG decreased cyclin E2 levels only in PC3 and DU-145 cells. It also altered Rb, H3, Wee1 and CDC2 phosphorylation in PCa cells. Intriguingly, AG reduced cell viability and the ability of PCa cells to migrate via modulating CXCL11 and CXCR3 and CXCR7 expression. The significant impact of AG on cellular and molecular processes involved in PCa progression suggests its potential use as a therapeutic and/or preventive agent for PCa.

CCR6 expression in colon cancer is associated with advanced disease and supports epithelial-to-mesenchymal transition

Background:Adjuvant chemotherapy offered to treat colon cancer is based on the TNM staging system, which often fails due to molecular heterogeneity and undefined molecular mechanisms independent of TNM. Therefore, identification of markers to better predict therapeutic option and outcome is needed. In this study we have characterised the clinical association of CCR6 with colon cancer and defined CCR6-mediated molecular pathway.Methods:Immunohistochemistry, RT-qPCR, western blot and FACS were used to determine expression of CCR6 and/or EMT markers in colon tissues/cells. BrdU assay and trans-well system were used to determine cell proliferation, migration and invasion in response to CCL20.Results:CCR6 was higher in cancer cases compared to normal adjacent tissue and expression was associated with nodal status and distant metastasis. Similarly, CCR6 expression was higher in cells derived from node-positive cases and highest expression was in cells derived from metastatic cases. Significant changes in EMT markers, that is, E-cadherin, vimentin, β-catenin, N-cadherin, α-SMA, SNAILl and ZEB1 were observed in response to CCL20 along with decreased proliferation, increased migratory and invasive potential.Conclusions:Results suggest CCR6 as a potential therapeutic target as well as biomarker in addition to nodal status for predicting therapeutic option.

Quercetin inhibits prostate cancer by attenuating cell survival and inhibiting anti-apoptotic pathways

BackgroundDespite recent advances in diagnosis and treatment, prostate cancer (PCa) remains the leading cause of cancer-related deaths in men. Current treatments offered in the clinics are often toxic and have severe side effects. Hence, to treat and manage PCa, new agents with fewer side effects or having potential to reduce side effects of conventional therapy are needed. In this study, we show anti-cancer effects of quercetin, an abundant bioflavonoid commonly used to treat prostatitis, and defined quercetin-induced cellular and molecular changes leading to PCa cell death.MethodsCell viability was assessed using MTT. Cell death mode, mitochondrial outer membrane potential, and oxidative stress levels were determined by flow cytometry using Annexin V-7 AAD dual staining kit, JC-1 dye, and ROS detection kit, respectively. Antibody microarray and western blot were used to delineate the molecular changes induced by quercetin.ResultsPCa cells treated with various concentrations of quercetin showed time- and dose-dependent decrease in cell viability compared to controls, without affecting normal prostate epithelial cells. Quercetin led to apoptotic and necrotic cell death in PCa cells by affecting the mitochondrial integrity and disturbing the ROS homeostasis depending upon the genetic makeup and oxidative status of the cells. LNCaP and PC-3 cells that have an oxidative cellular environment showed ROS quenching after quercetin treatment while DU-145 showed rise in ROS levels despite having a highly reductive environment. Opposing effects of quercetin were also observed on the pro-survival pathways of PCa cells. PCa cells with mutated p53 (DU-145) and increased ROS showed significant reduction in the activation of pro-survival Akt pathway while Raf/MEK were activated in response to quercetin. PC-3 cells lacking p53 and PTEN with reduced ROS levels showed significant activation of Akt and NF-κB pathway. Although some of these changes are commonly associated with oncogenic response, the cumulative effect of these alterations is PCa cell death.ConclusionsOur results demonstrated quercetin exerts its anti-cancer effects by modulating ROS, Akt, and NF-κB pathways. Quercetin could be used as a chemopreventive option as well as in combination with chemotherapeutic drugs to improve clinical outcomes of PCa patients.

Abstract 4642: Quercetin inhibits prostate cancer by modulating molecules involved in apoptosis and cell proliferation

Prostate cancer (PCa) remains the second leading cause of death in men, despite the multimodal options offered in the clinics. Long latency and indolent nature of PCa provides window of opportunity for preventive interventions using natural and synthetic agents. Quercetin, a bioflavonoid abundant in fruits and vegetables, has been reported to inhibit growth in cancer and reduce inflammation in conditions like prostatitis. Considering this, we investigated the chemo-preventive effects of Quercetin on PCa. The effects of Quercetin on apoptosis and associated proteins on both RNA and protein levels were determined using apoptosis assay, real-time qPCR and western blot, respectively. Furthermore, an antibody microarray was performed to observe changes induced by Quercetin on signaling molecules and possible mechanism of cell survival/apoptosis in PCa. PCa cells treated with Quercetin showed decreased cell proliferation in a time and dose dependent manner, while no significant effect was seen on normal prostate cells. Quercetin treatment also significantly induced apoptosis in PCa cells, as compared with untreated controls. Different phosphorylation status of key molecules (Bcl-2, Akt-1 and NF-k B) was observed following Quercetin treatment in PCa cell lines, as compared with untreated controls, which are known to be involved in supporting PCa progression. These results suggest that Quercetin could be a potential chemo-preventative agent capable of slowing down the progression of PCa, by increasing apoptosis and decreasing cell proliferation. Note: This abstract was not presented at the meeting. Citation Format: Ashely B. Ward, Hina Mir, Neeraj Kapur, Shailesh Singh. Quercetin inhibits prostate cancer by modulating molecules involved in apoptosis and cell proliferation. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4642. doi:10.1158/1538-7445.AM2015-4642

Abstract 2128: The effects of Quercetin on prostate cancer

Prostate cancer (PCa) affects nearly 80% of men worldwide and is the second leading killer after lung cancer. The efficacy of current treatments offered in the clinics is highly compromised due to indolent nature of PCa, which provides large window of opportunity for prevention. Hence, the major focus of this study is to determine the chemo-preventive effects of Quercetin, a bioflavonoid, on prostate cancer. Effect of Quercetin on cell viability and IC50 was determined by MTT assay. The effect of Quercetin on cell motility was determined by wound healing assay. Potential role of Quercetin on cell cycle, apoptosis as well as genes involved in cell motility and invasion was determined using flow cytometry, Real-time qPCR and ELISA. Furthermore, Quercetin induced changes in signaling molecules involved in cell survival/apoptosis, cell cycle and cytoskeletal rearrangement was determined using antibody microarray. Prostate cancer cells treated with Quercetin showed dose and time dependent inhibition of proliferation/viability, and induction of apoptosis as compared to normal prostatic epithelial cells and untreated controls. Prostate cancer cell motility was inhibited in Quercetin treated cells. Prostate cancer cells were arrested in G2 phase of the cell cycle following Quercetin treatment. In addition to these, we found differential expression of caspases, matrix metalloproteinases (MMPs) and tissue inhibitor of MMPs in different PCa cell lines compared to untreated controls. Furthermore, antibody microarray analysis demonstrated selective modulation of genes and associated signaling cascades responsible for apoptosis induction, cellular motility, adhesion and invasion in Quercetin treated cells compared to controls. These findings suggest Quercetin as a potent chemo-preventive agent. In addition to this it can be also used with chemotherapeutic agents directed to G2 phase of the cell cycle, which may improve the efficacy of chemotherapeutics offered in clinics to treat advance prostate cancer. Citation Format: Ashley B. Ward, Pranav Gupta, Gurpreet Kaur, Hina Mir, James W. Lillard, Shailesh Singh. The effects of Quercetin on prostate cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2128. doi:10.1158/1538-7445.AM2014-2128

Abstract 4003: Clinical and biological significance of CXCR6 in lung cancer

Lung cancer is the leading cause of cancer related deaths worldwide in both men and women. Metastasis is responsible for most lung cancer related deaths; therefore, a better understanding of the metastatic processes and therapies designed to prevent the spread of cancer cells are greatly needed. The specific mechanisms that promote metastases have not been fully elucidated. Among all known chemokine receptors involved in cancer progression, most cancer cells including lung cancer express CXCR4. Furthermore, involvement of CXCR4 and CCR7 in breast cancer and CXCR4, CCR9 and CX3CR1 in prostate cancer progression further indicates that multiple chemokine receptors are involved in dictating the multi-step process of metastasis. In this study, we show significantly higher expression of CXCR6 and CXCL16 in lung cancer tissues compared to normal matched tissues. Expression of CXCR6 was significantly higher in adeno- carcinoma compared to squamous cell carcinoma. It addition to these, serum levels of CXCL16, the only natural ligand for CXCR6, was also significantly higher in lung cancer patients compared to normal healthy donor. Furthermore, serum CXCL16 was also significantly higher in patients with adenocarcinoma compared to patients with squamous cell carcinoma. Impact of this chemokines-receptor axis was determined in lung cancer cell lines in vitro, which express CXCR6 and CXCL16. Like tissues, lung cancer cells showed higher expression of CXCR6 and CXCL16 compared to normal lung epithelial cells (NuLi-1). Interestingly, expression of CXCR6 was highest in cell lines derived form adenocarcinoma followed by cell lines from squamous cell carcinoma. Furthermore, we demonstrate that CXCR6 and soluble CXCL16 interaction plays a crucial role in lung cancer cells migration and invasion. The mechanism underlying these clinically and biologically important findings need to be further explored. Increased serum CXCL16 in lung cancer patients with metastatic disease required further validation as a potential therapeutic target and/or diagnostic marker for lung cancer. Citation Format: Hina Mir, Pranav Gupta, Rajesh Singh, Praveen K. Sharma, Gurpreet Kaur, Ashley B. Ward, William E. Grizzle, James W. Lillard, Shailesh Singh. Clinical and biological significance of CXCR6 in lung cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4003. doi:10.1158/1538-7445.AM2014-4003

Cinnamtannin B-1 inhibits cell survival molecules and induces apoptosis in colon cancer

Colon cancer patients receiving chemotherapy continue to be burdened with therapeutic failure and adverse side effects, yielding a need to develop more effective treatments. The present study investigates Cinnamtannin B-1 (CTB-1) as a potential low-toxicity therapeutic alternative for colon cancer. CTB-1-treated DLD-1, COLO 201 and HCT-116 (WT p53 and p53 null) colon cancer cells and CCD 841 CoN normal colon epithelial cells were assessed for changes in survival using MTT assay. The effects of CTB-1 on cell cycle progression and the apoptosis of colon cancer cells were measured using flow cytometry and/or immunofluorescence. The expression profiles of cell survival molecules, particularly apoptotic proteins, in the colon cancer cells were evaluated following CTB-1 treatment via antibody array, then validated by western blot analysis. Additionally, the potential synergy between CTB-1 and 5-fluorouracil (5-FU), a conventional chemotherapeutic agent used in the treatment of colon cancer, against colon cancer cells was assessed using MTT assay and Calcusyn software. The results revealed that CTB-1 signifi-cantly decreased the survival of the DLD-1, COLO 201 and HCT-116 cells in a time and/or dose-dependent manner, with minimal cytotoxicity to normal colon cells. CTB-1 treatment was shown to induce cell cycle arrest and apoptosis of DLD-1 and COLO 201 cells. Of note, CTB-1 modulated the expression of several cell survival molecules, which tend to be deregulated in colon cancer, including p53, a key transcription factor involved in apoptosis. The downstream regulation of Bcl-2 and Bak expression, as well as cytochrome c release into the cytosol, was also observed following CTB-1 treatment. Furthermore, CTB-1 was shown to significantly enhance the potency of 5-FU via a synergistic drug interaction. This study reveals for the first time, to the best of our knowledge, the ability of CTB-1 to decrease the survival of colon cancer cells through pro-apoptotic mechanisms and display synergy with conventional chemotherapy, demonstrating the potential therapeutic benefit of CTB-1 in colon cancer.

Association of Cytokines and Chemokines in Pathogenesis of Breast Cancer

Breast cancer touches womens life worldwide. Expected outcome is not achieved due to molecular heterogeneity and complex biology despite substantial advancement in diagnosis, prevention and treatment of breast cancer. Patients with estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (Her2) positive tumors receive hormone ablation and Her2 directed therapy. While patients diagnosed with triple-negative breast cancer receive chemotherapy in both the early and advanced stages. However, chemotherapeutic efficacies are not the same in every patient, which has fostered a major effort to identify new targets to treat breast cancer. Positive therapeutic outcome after immune checkpoint inhibitors emphasizes the significance of the host immune system in breast cancer. Cancer develops in immune competent host wherein cytokines, while shaping the immune system, also serve as growth signals for cancer cells. The dynamics of cross talk between immune system and cancer cells mediated by cytokines and chemokines changes during cancer initiation, progression, and therapeutic interventions. Hence, better understanding of molecular footprint of cancer cells, as well as crosstalk between cancer cells and host immune system is needed to develop patient specific treatment and management of breast cancer.

Abstract 5252: Quercetin inhibits prostate cancer by modulating ROS and key regulators of apoptosis and cell survival

Long latency and indolent nature of prostate cancer (PCa) provides a window of opportunity for preventive interventions using natural and synthetic agents. Hence, the focus of this study was to ascertain the chemopreventive role of Quercetin, a bioflavonoid, commonly used to treat prostatitis. Human PCa cells (LNCaP, DU145 and PC3) were treated with different concentrations of Quercetin and its effect on cell survival and apoptosis was determined by MTT assay. Human PCa cells treated with Quercetin showed significant reduction in cell viability and proliferation compared with untreated controls, which was dose and time dependent. In addition to this our FACS analysis showed higher percentage of apoptotic cells after Quercetin treatment compared to untreated cells. Quercetin induced apoptosis in PCa cells is a cumulative effect of modulation of key apoptotic proteins, changes in mitochondrial membrane potential and ROS production. Our results demonstrate that Quercetin is a potent chemopreventive agent, which may improve outcomes of PCa by inhibiting mechanisms involved in tumor progression. Citation Format: Ashley B. Ward, Hina Mir, Neeraj Kapur, Guru Sonpavde, Shailesh Singh. Quercetin inhibits prostate cancer by modulating ROS and key regulators of apoptosis and cell survival [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5252. doi:10.1158/1538-7445.AM2017-5252