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Objective: Advanced cervical cancer is still difficult to treat and in the case of recurrent cancer, it is desirable to utilize personalized treatment rather than uniform treatment because the type of recurrence is different for each individual. Therefore, this study aimed to establish patients-derived organoid platform to determine the effects of chemotherapy, radiation therapy, and targeted therapy in cervical cancer. Methods: We established organoids from four patients with various types of cervical cancer. The histopathological and gene profiles of these organoid models were compared to determine their characteristics and the maintenance of the patient phenotype. Each type of organoid was also subjected to anticancer drug screening and radiation therapy to evaluate its sensitivity. Results: We established patient-derived organoids recapitulated the main elements of the original patient tumors, including the DNA copy number and mutational profile. We screened seven drugs that showed growth inhibition in cervical cancer organoids using two analytical tools (individual drugs and an FDA-approved drug library). Moreover, squamous cell carcinoma and villoglandular carcinoma showed significant response to radiation therapy, however, adenocarcinoma and large-cell neuroendocrine carcinoma showed relative resistance to radiation therapy. Conclusion: Our results showed patient-derived cervical cancer organoid can be used as a pre-clinical model for drug and radiation sensitivity test. These findings suggest that patient-derived cervical cancer organoids could be used as a personalized medicine confirmation tool and to improve treatment options for patients with various subtypes of cervical cancer. Citation Format: Ju Hee Oh, Hyang Sook Seol, Eun Hye Choi, Yong Jae Lee Lee, Jung-Yun Lee, Sang Wun Kim, Sunghoon Kim, Young Tae Kim, Hyun Ki Kim, Young Joo Lee, Eun Ji Nam. Patient-derived cervical cancer organoids as a pre-clinical model predicting drug and radiation response [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 200.

// Jaeyun Jung 1, * , Cue Hyunkyu Lee 3, * , Hyang Sook Seol 4 , Yeon Sook Choi 4 , Eunji Kim 3, 5 , Eun Ji Lee 1 , Je-Keun Rhee 6 , Shree Ram Singh 7 , Eun Sung Jun 1 , Buhm Han 3 , Seung Mo Hong 8 , Song Cheol Kim 9 , Suhwan Chang 1, 2 1 Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul, Korea 2 Department of Physiology, University of Ulsan College of Medicine, Seoul, Korea 3 Department of Convergence Medicine, University of Ulsan College of Medicine, Seoul, Korea 4 Asan Institute for Life Sciences, Asan Medical Center, Seoul, Korea 5 Department of Chemistry, Seoul National University, Seoul, Korea 6 Department of Medical Informatics, College of Medicine, The Catholic University of Korea, Seoul, Korea 7 Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, MD, USA 8 Department of Pathology, Asan Medical Center, Seoul, Korea 9 Department of Surgery, Asan Medical Center, Seoul, Korea * These authors have contributed equally to this work Correspondence to: Song Cheol Kim, email: drksc@amc.seoul.kr Suhwan Chang, email: suhwan.chang@amc.seoul.kr Keywords: pancreatic cancer, patient-derived xenograft, single nucleotide polymorphism, cancer panel, heterogeneity Received: June 01, 2016 Accepted: August 08, 2016 Published: August 23, 2016 ABSTRACT Pancreatic ductal adenocarcinoma (PDAC) is the most challenging type of cancer to treat, with a 5-year survival rate of

Tumor-initiating cells are important for the formation and maintenance of tumor bulks in various tumors. To identify surface markers of liver tumor-initiating cells, we performed primary tumorsphere culture and analyzed the expression of cluster of differentiation (CD) antigen genes using NanoString. Interestingly, we found significant upregulation of the complement proteins (p = 1.60 × 10(-18)), including C7 and CFH. Further studies revealed that C7 and CFH are required to maintain stemness in liver cancer cells. Knockdown of C7 and CFH expression abrogated tumorsphere formation and induced differentiation, whereas overexpression stimulated stemness factor expression as well as in vivo cell growth. Mechanistically, by studying C7 and CFH-dependent LSF-1 expression and its direct role on stemness factor transcription, we found that LSF-1 is involved in this regulation. Taken together, our data demonstrate the unprecedented role of complement proteins on the maintenance of stemness in liver tumor-initiating cells.

Establishing an appropriate preclinical model is crucial for translational cancer research. The most common way that has been adopted by far is grafting cancer cell lines, derived from patients. Although this xenograft model is easy to generate, but has several limitations because this cancer model could not represent the unique features of each cancer patient sufficiently. Moreover, accumulating evidences demonstrate cancer is a highly heterogeneous disease so that a tumor is comprised of cancer cells with diverse characteristics. In attempt to avoid these discrepancies between xenograft model and patients' tumor, a patient-derived xenograft (PDX) model has been actively generated and applied. The PDX model can be developed by the implantation of cancerous tissue from a patient's tumor into an immune-deficient mouse directly, thereby it preserves both cell-cell interactions and tumor microenvironment. In addition, the PDX model has shown advantages as a preclinical model in drug screening, biomarker development and co-clinical trial. In this review, we will summarize the methodology and applications of PDX in detail, and cover critical issues for the development of this model for preclinical research.

Background Preclinical trials of cancer therapeutics require both in vitro and in vivo evaluations. Recently, a patient-derived xenograft model in immunodeficient mice has been reported as a valuable in vivo evaluation system. In our current study, we aimed to establish a more efficient and accurate system for preclinical trials by generating primary cancer cells from patients and performing xenograft transfers of these cells into mice. Methods Human lung cancer specimens (n = 4) obtained from chemo-naive patients were cultured in bronchiolar epithelial basal medium supplemented with growth factors, followed by inoculation into non-obese diabetic/severe combined immunodeficient mice. The generated tumors in the mice were validated phenotypically and genetically using the original specimen and primary cancer cells. Results Immunohistochemical analysis of marker proteins, including cytokeratin 7, cytokeratin 20, epidermal growth factor receptor, thyroid transcription factor-1, CD56, chromogranin, and synaptophysin, demonstrated that the xenograft tumors were originated from the patient tumors. Moreover, mutation profiling using the OncoMap System, which analyzes mutations at 440 sites in 41 tumorrelated genes, showed the same patterns in both the patient and xenograft tumors. Conclusions These results indicate that our animal system is suitable for the amplification of patient tumors and will therefore be beneficial for both in vivo and in vitro assessments and preclinical trials of chemotherapeutics. This has the potential to provide a very effective tool for future personalized therapy and for conducting translational lung cancer research.

Liver cancer is one of the common malignancies in many countries and an increasing cause of cancer death. Despite of that, there are few therapeutic options available with inconsistent outcome, raising a need for developing alternative therapeutic options. Through a drug repositioning screening, we identified and investigated the action mechanism of the Riluzole, an amyotrophic lateral sclerosis (ALS) drug, on hepatocellular carcinoma (HCC) therapy. Treatment of the Riluzole leads to a suppression of cell proliferation in liver primary cancer cells and cancer cell lines. In addition, Riluzole induced caspase-dependent apoptosis and G2/M cell cycle arrest in SNU449 and Huh7 cell lines. In a line with the known function of glutamate release inhibitor, we found Riluzole-treated cells have increased the level of inner cellular glutamate that in turn decrease the glutathione (GSH) level and finally augment the reactive oxygen species (ROS) production. We confirm this finding in vivo by showing the Riluzole-induced GSH and ROS changes in a Huh7 xenograft cancer model. Altogether, these data suggest the anti-cancer effect of Riluzole on hepatocellular carcinoma and the suppression of glutamate signaling might be a new target pathway for HCC therapy.

Microarray analyses have revealed significantly elevated expression of the proto-oncogene ROS1 receptor tyrosine kinase in 20–30 % of non-small cell lung carcinomas (NSCLC). Selective and potent ROS1 kinase inhibitors have recently been developed and oncogenic rearrangement of ROS1 in NSCLC identified. We performed immunohistochemical evaluation of expression of ROS1 kinase and its downstream molecules in 399 NSCLC cases. ROS1 expression in primary and recurring lesions of 92 recurrent NSCLC cases was additionally analyzed. To elucidate mechanism of expression, two ROS1-nonexpressing NSCLC cell lines (Calu6 and H358) and fresh frozen tissues from 28 consecutive NSCLC patients were examined for ROS1 promoter methylation status and ROS1 expression. Overall expression rate of ROS1 was 22 % (19 % for adenocarcinomas and 25 % for nonadenocarcinomas) in NSCLC. ROS1 expression was a worse prognostic factor for overall survival in adenocarcinomas of stage I NSCLC. In recurred NSCLC, ROS1 expression was significantly higher in recurring tumors (38 %) than primary tumors (19 %). Two NSCLC cell lines showed increased ROS1 expression after treatment with 5-aza-2′deoxycytidine and/or trichostatin A. Among the 14 adenocarcinomas examined, two (14 %) showed more than twice the level of ROS1 expression in tumor tissue than was observed in matched normal tissue and statistically significant differences in the ROS1 promoter methylation level. A subset of NSCLC revealed overexpression of ROS1 receptor tyrosine kinase, possibly in relation to epigenetic changes. ROS1 expression was an independent prognostic factor for overall survival in adenocarcinomas of stage I NSCLC. Further studies are needed to validate our results.

The role of microRNAs (miRNAs) in carcinogenesis as tumor suppressors or oncogenes has been widely reported. Epigenetic change is one of the mechanisms of transcriptional silencing of miRNAs in cancer. To identify lung cancer-related miRNAs that are mediated by histone modification, we conducted microarray analysis in the Calu-6 non-small cell lung cancer (NSCLC) cell line after treatment with suberoylanilide hydroxamic acid (SAHA), a histone deacetylase (HDAC) inhibitor. The expression level of miR-373 was enhanced by SAHA treatment in this cell line by microarray and the following quantitative RT-PCR analyses. Treatment with another HDAC inhibitor, Trichostatin A, restored the levels of miR-373 expression in A549 and Calu-6 cells, while demethylation drug treatment did not. Importantly, miR-373 was found to be down-regulated in NSCLC tissues and cell lines. Transfection of miR-373 into A549 and Calu-6 cells attenuated cell proliferation, migration, and invasion and reduced the expression of mesenchymal markers. Additional microarray analysis of miR-373-transfected cells and computational predictions identified IRAK2 and LAMP1 as targets of miR-373. Knockdown of these two genes showed similar biological effects to those of miR-373 overexpression. In clinical samples, overexpression of IRAK2 correlated with decreased disease-free survival of patients with non-adenocarcinoma. In conclusion, we found that miR-373 is silenced by histone modification in lung cancer cells and identified its function as a tumor suppressor and negative regulator of the mesenchymal phenotype through downstream IRAK2 and LAMP1 target genes.

Cultures of primary tumors are very useful as a personalized screening system for effective therapeutic options. We here describe an effective method of reproducing human primary colon tumors through primary culture and a mouse xenograft model. A total of 199 primary colon tumor cultures were successfully established under optimized conditions to enrich for tumor cells and to expand it for long-term storage in liquid nitrogen. To examine whether these stored cultures retained original tumor properties, fifty primary cultures were xenografted into NOD-SCID mouse. Histological and tumor marker analysis of four representative tumor xenografts revealed that all of the xenograft retained its primary tumor characteristics. Oncomap analysis further showed no change in the major mutations in the xenografts, confirming that our method faithfully reproduced human colon tumors. A drug sensitivity assay revealed that two of the primary cultures were hypersensitive to oxaliplatin rather than 5-FU, which was used in the patients, suggesting it as an effective therapeutic option. We thus present an effective, reproducible preclinical model for testing various personalized therapeutic options in colon cancer patients.

Identification of gastric tumor-initiating cells (TICs) is essential to explore new therapies for gastric cancer patients. There are reports that gastric TICs can be identified using the cell surface marker CD44 and that they form floating spheres in culture, but we could not obtain consistent results with our patient-derived tumor xenograft (PDTX) cells. We thus searched for another marker for gastric TICs, and found that CD49f(high) cells from newly-dissected gastric cancers formed tumors with histological features of parental ones while CD49f(low) cells did not when subcutaneously injected into immunodeficient mice. These results indicate that CD49f, a subunit of laminin receptors, is a promising marker for human gastric TICs. We established a primary culture system for PDTX cells where only CD49f(high) cells could grow on extracellular matrix (ECM) to form ECM-attaching spheres. When injected into immunodeficient mice, these CD49f(high) sphere cells formed tumors with histological features of parental ones, indicating that only TICs could grow in the culture system. Using this system, we found that some sphere-forming TICs were more resistant than gastric tumor cell lines to chemotherapeutic agents, including doxorubicin, 5-fluorouracil and doxifluridine. There was a patient-dependent difference in the tumorigenicity of sphere-forming TICs and their response to anti-tumor drugs. These results suggest that ECM plays an essential role for the growth of TICs, and that this culture system will be useful to find new drugs targeting gastric TICs.

Wip1 (wild-type p53-induced phosphatase, or PPM1D) belongs to the protein phosphatase type 2C family and its expression is induced by p53 in response to various stresses. Wip1 is known to dephosphorylate cellular target proteins such as p38 MAPK, p53, and uracil DNA glycosylase that are involved in DNA-repair and cell-cycle-checkpoint pathways. Here, we show that after methylmethane sulfonate (MMS) treatment Wip1 is induced in various breast-cancer cell lines in the absence of wild-type p53 and p38 MAPK activity. Wip1 expression in response to MMS was not blocked by the p38 MAPK inhibitor SB202190 or in p38-silenced MCF-7 cells using p38 MAPK small-interfering RNA (siRNA). The Wip1 promoter displayed great induction in breast cancer cell lines, which have DNA-binding deficient p53 mutants, and p53-null cancer cells such as Saos-2, A549-E6 and HCT116(p53−/−), whereas a control promoter, p53-Luc, showed the least promoter activity after MMS treatment. The mutation of p53 response element in the Wip1 promoter decreased its activity in both unstressed and stressed cells, but the overall level of fold-induction was similar. In addition, cell death was greatly increased in Wip1-siRNA and MMS treated cells in comparison with scrambled siRNA and MMS treated cells in the both cell lines of HCT116 (p53 +/+) and HCT116 (p53−/−). Our data indicate that Wip1 induction in response to various stimuli is not solely controlled by p53, and other damage response signaling appears to compensate for p53. Furthermore, Wip1 negatively regulates DNA-damage induced cell death regardless of the presence wild-type p53. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2987.