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Abstract Background Next-generation sequencing (NGS) has been introduced to many Korean institutions to support molecular diagnostics in cancer since 2017, when it became eligible for reimbursement by the National Health Insurance Service. However, the uptake of molecularly guided treatment (MGT) based on NGS results has been limited because of stringent regulations regarding prescriptions outside of approved indications, a lack of clinical trial opportunities, and limited access to molecular tumor boards (MTB) at most institutions. The KOSMOS-II study was designed to demonstrate the feasibility and effectiveness of MGT, informed by MTBs, using a nationwide precision medicine platform. Methods The KOSMOS-II trial is a large-scale nationwide master observational study. It involves a framework for screening patients with metastatic solid tumors for actionable genetic alterations based on local NGS testing. It recommends MGT through a remote and centralized MTB meeting held biweekly. MGT can include one of the following options: Tier 1, the therapeutic use of investigational drugs targeting genetic alterations such as ALK, EGFR, ERBB2, BRAF, FH, ROS1, and RET, or those with high tumor mutational burden; Tier 2, comprising drugs with approved indications or those permitted for treatment outside of the indications approved by the Health Insurance Review and Assessment Service of Korea; Tier 3, involving clinical trials matching the genetic alterations recommended by the MTB. Given the anticipated proportion of patients receiving MGT in the range of 50% ± 3.25%, this study aims to enroll 1,000 patients. Patients must have progressed to one or more lines of therapy and undergone NGS before enrollment. Discussion This pragmatic master protocol provides a mass-screening platform for rare genetic alterations and high-quality real-world data. Collateral clinical trials, translational studies, and clinico-genomic databases will contribute to generating evidence for drug repositioning and the development of new biomarkers. Trial registration NCT05525858.

Abstract Background For locally advanced rectal cancer (LARC), total neoadjuvant therapy (TNT) may enhance tumour response, reduce recurrence, and improve patient compliance compared to upfront surgery. Recent studies have shown that chemoradiotherapy (CRT) followed by consolidation chemotherapy leads to higher rate of pathologic complete response (pCR) than induction chemotherapy followed by CRT. However, an optimal TNT regimen that maximise the pCR rate and minimise toxicity has not been established. Therefore, the aim of this trial was to investigate whether preoperative short-course radiotherapy followed by chemotherapy with four cycles of CAPOX can double the pCR rate compared to a standard schedule of long-course preoperative CRT in patients with LARC. Methods This is a multi-centre, prospective, open label, randomised controlled trial. Patients with clinical primary tumour stage 3 and higher or regional node-involved rectal cancer located within 10 cm from the anal verge were randomly assigned equally to short-course radiotherapy (25 Gy in 5 fractions over 1 week) followed by four cycles of CAPOX (intravenous oxaliplatin [130 mg/m2, once a day] on day 1 and capecitabine [1,000 mg/m2, twice a day] from days 1 to 14) (TNT) or CRT (50.4 Gy in 28 fractions over 5 weeks, concurrently with concomitant oral capecitabine 825 mg/m2 twice a day). After preoperative treatment, total mesorectal excision was performed 2–4 weeks in the TNT group and 6–10 weeks in the CRT group, followed by optional additional adjuvant chemotherapy. The primary endpoint is the pCR rate, and secondary endpoints include disease-related treatment failure, quality of life, and cost-effectiveness. Assuming a pCR rate of 28% and 15% in the TNT and CRT groups, respectively, and one-side alpha error rate of 0.025 and power of 80%, 348 patients will be enrolled considering 10% dropout rate. Discussion The TV-LARK trial will evaluate the superiority of employed TNT regimen against the standard CRT regimen for patients with LARC. We aimed to identify a TNT regimen that will improve the pCR rate and decrease systemic recurrence in these patients. Trial registration Cris.nih.go.kr ID: KCT0007169 (April 08, 2022). The posted information will be updated as needed to reflect the protocol amendments and study progress.

Purpose The aim of this study was to assess the role of the shear-wave velocity (SWV) value in predicting chemotherapeutic response and progression-free survival (PFS) in patients with colorectal cancer liver metastasis (CRLM). Methods In this prospective single-center study, participants with CRLM scheduled for chemotherapy were enrolled between May 2018 and June 2021. SWV measurements were obtained using shear-wave elastography at the CRLM site before and after initiating chemotherapy. Based on the Response Evaluation Criteria in Solid Tumors, the participants were categorized by chemotherapeutic response into responders (complete remission and partial remission) and non-responders (stable disease and progressive disease). Receiver operating characteristic (ROC) curve analysis was conducted to evaluate the performance of changes in SWV measurements in predicting the chemotherapeutic response of CRLM. In addition, a Cox proportional hazards model was used to identify variables associated with PFS. Results In total, 67 participants (40 men; mean age, 62.3±10.1 years) were enrolled, including 34 responders and 33 non-responders. The area under the ROC curve, sensitivity, and negative predictive value of the SWV measurement in predicting non-responders were 0.840, 97.0%, and 95.2%, respectively, using a cutoff value of a 13% decrease. Additionally, a change in SWV values was independently associated with PFS (hazard ratio, 1.020), non-responder status, and the presence of five or more CRLMs. Conclusion A change in SWV values measured after chemotherapy demonstrated meaningful diagnostic performance in predicting non-responsiveness among patients with CRLM. Additionally, a change in SWV values was independently associated with PFS.

Patient‐derived organoids are being considered as models that can help guide personalized therapy through in vitro anticancer drug response evaluation. However, attempts to quantify in vitro drug responses in organoids and compare them with responses in matched patients remain inadequate. In this study, we investigated whether drug responses of organoids correlate with clinical responses of matched patients and disease progression of patients. Organoids were established from 54 patients with colorectal cancer who (except for one patient) did not receive any form of therapy before, and tumor organoids were assessed through whole‐exome sequencing. For comparisons of in vitro drug responses in matched patients, we developed an ‘organoid score’ based on the variable anticancer treatment responses observed in organoids. Very interestingly, a higher organoid score was significantly correlated with a lower tumor regression rate after the standard‐of‐care treatment in matched patients. Additionally, we confirmed that patients with a higher organoid score (≥ 2.5) had poorer progression‐free survival compared with those with a lower organoid score (

Abstract Circulating tumor DNA (ctDNA) may reveal dynamic tumor status during therapy. We conducted serial ctDNA analysis to investigate potential association with clinical outcome in metastatic colorectal cancer (mCRC) patients receiving chemotherapy. Tissue KRAS/NRAS wild-type mCRC patients were enrolled and treated with first-line cetuximab-containing chemotherapy. ctDNA isolated from plasma were analyzed by next generation sequencing (NGS) with 16 targeted gene panel. Among 93 patients, 84 (90.3%) had at least 1 somatic mutation in baseline ctDNA samples (average 2.74). Five patients with KRAS or NRAS hotspot mutation in the ctDNA showed significantly worse progression-free survival (PFS) (p = 0.029). Changes in average variant allele frequency (VAF) in ctDNA showed significant correlation with tumor size change at the time of first response evaluation (p = 0.020) and progressive disease (PD) (p = 0.042). Patients whose average VAF decreased below cutoff (

Abstract Several studies have reported that the prognostic effect of KRAS mutations on colorectal cancers (CRCs) varies depending on the type of mutation. Considering the effect of KRAS mutations on tumor microenvironment, we analyzed the prognostic significance of KRAS mutation types after adjusting for the tumor-infiltrating lymphocytes (TIL) and tumor-stromal percentage (TSP) statuses. In two independent cohorts, KRAS mutations were analyzed by Sanger sequencing and/or next-generation sequencing. TIL density and the TSP were quantified from whole-slide immunohistochemical images. KRAS-mutant CRCs were divided into three subgroups (G12D/V, other codon 12 mutations and codon 13 mutations) to examine their differential effect on TIL density, the TSP and recurrence-free survival (RFS). Among the KRAS mutations, only the G12D/V subgroups showed significantly less TIL infiltration than the wild-type CRCs. According to survival analysis, G12D/V mutations were associated with short RFS; codon 13 mutations showed discordant trends in the two cohorts, and other codon 12 mutations showed no significant association. Multivariate analysis further supported the prognostic value of G12D/V mutations. This result is not only consistent with a recent study suggesting the immunosuppressive effect of mutant KRAS but also provides insight into the type-specific prognostic effect of KRAS mutations.

Abstract Background Although the prognostic biomarkers associated with colorectal cancer (CRC) survival are well known, there are limited data on the association between the molecular characteristics and survival after recurrence (SAR). The purpose of this study was to assess the association between pathway mutations and SAR. Methods Of the 516 patients with stage III or high risk stage II CRC patients treated with surgery and adjuvant chemotherapy, 87 who had distant recurrence were included in the present study. We analyzed the association between SAR and mutations of 40 genes included in the five critical pathways of CRC (WNT, P53, RTK-RAS, TGF-β, and PI3K). Results Mutation of genes within the WNT, P53, RTK-RAS, TGF-β, and PI3K pathways were shown in 69(79.3%), 60(69.0%), 57(65.5%), 21(24.1%), and 19(21.8%) patients, respectively. Patients with TGF-β pathway mutation were younger and had higher incidence of mucinous adenocarcinoma (MAC) histology and microsatellite instability-high. TGF-β pathway mutation (median SAR of 21.6 vs. 44.4 months, p = 0.021) and MAC (20.0 vs. 44.4 months, p = 0.003) were associated with poor SAR, and receiving curative resection after recurrence was associated with favorable SAR (Not reached vs. 23.6 months, p

Pruritus is a very common symptom in patients, undergoing targeted anticancer therapy. However, the characteristics of pruritus, according to the targeted anticancer agents, are still unclear. The objective of this study was to determine the characteristics of pruritus, induced by targeted anticancer agents, using a questionnaire-based survey. The survey was administered to cancer patients currently receiving anticancer agents. Medical records were also reviewed. A total of 374 cancer patients completed the survey, of which 108 were treated with the targeted therapy. A total of 205 patients had pruritus, of which 66 were under the targeted therapy. Epidermal growth factor receptor inhibitor (EGFRI) users showed the highest prevalence rate of itching and numeric rating scale score for itching. The 5-D itch score was also highest among users of EGFRIs. In conclusion, patients receiving EGFRIs suffer from severe pruritus frequently. They not only experienced long lasting and intense itching, causing sleep discomfort, but also developed itching at specific body sites.

Analyzing cell-free DNA (cfDNA) as a source of circulating tumor DNA is useful for diagnosing or monitoring patients with cancer. However, the concordance between cfDNA within liquid biopsy and genomic DNA (gDNA) within tumor tissue biopsy is still under debate. To evaluate the concordance in a clinical setting, we enrolled 54 patients with metastatic colorectal cancer and analyzed their plasma cfDNA, gDNA from peripheral blood mononuclear cells (PBMC), and gDNA from available matched tumor tissues using ultra-deep sequencing targeting 10 genes (38-kb size) recurrently mutated in colorectal cancer. We first established a highly reliable cut-off value using reference material. The sensitivity of detecting KRAS hotspot mutations in plasma was calculated as 100%, according to digital droplet PCR. We could selectively detect clinically important somatic alterations with a variant allele frequency as low as 0.18%. We next compared somatic mutations of the 10 genes between cfDNA and genomic DNA from tumor tissues and observed an overall 93% concordance rate between the two types of samples. Additionally, the concordance rate of patients with the time interval between liquid biopsy and tumor tissue biopsy within 6 months and no prior exposure to chemotherapy was much higher than those without. The patients with KRAS mutant fragments in plasma had poor prognosis than those without the mutant fragments (33 months vs. 63 months; p

Although MEK blockade has been highlighted as a promising antitumor drug, it has poor clinical efficacy in KRAS mutant colorectal cancer (CRC). Several feedback systems have been described in which inhibition of one intracellular pathway leads to activation of a parallel signaling pathway, thereby decreasing the effectiveness of single‐MEK targeted therapies. Here, we investigated a bypass mechanism of resistance to MEK inhibition in KRAS CRC. We found that KRAS mutant CRC cells with refametinib, MEK inhibitor, induced MIF secretion and resulted in activation of STAT3 and MAPK. MIF knockdown by siRNA restored sensitivity to refametinib in KRAS mutant cells. In addition, combination with refametinib and 4‐IPP, a MIF inhibitor, effectively reduced the activity of STAT3 and MAPK, more than single‐agent treatment. As a result, combined therapy was found to exhibit a synergistic growth inhibitory effect against refametinib‐resistant cells by inhibition of MIF activation. These results reveal that MIF‐induced STAT3 and MAPK activation evoked an intrinsic resistance to refametinib. Our results provide the basis for a rational combination strategy against KRAS mutant colorectal cancers, predicated on the understanding of cross talk between the MEK and MIF pathways.

Although regorafenib has demonstrated survival benefits in patients with metastatic colorectal and gastrointestinal stromal tumors, no proven biomarker has been identified for predicting sensitivity to regorafenib. Here, we investigated preclinical activity of regorafenib in gastric and colorectal cancer cells to identify genetic alterations associated with sensitivity to regorafenib. Mutation profiles and copy number assays of regorafenib target molecules indicated that amplification of fibroblast growth factor receptor 2 (FGFR2) was the only genetic alteration associated with in vitro sensitivity to regorafenib. Regorafenib effectively inhibited phosphorylation of FGFR2 and its downstream signaling molecules in a dose‐dependent manner and selectively in FGFR2‐amplified cells. Regorafenib induced G1 arrest (SNU‐16, KATO‐III) and apoptosis (NCI‐H716); however, no significant changes were seen in cell lines without FGFR2 amplification. In SNU‐16 mice xenografts, regorafenib significantly inhibited tumor growth, proliferation, and FGFR signaling compared to treatment with control vehicle. Regorafenib effectively abrogates activated FGFR2 signaling in FGFR2‐amplified gastric and colorectal cancer and, therefore, might be considered for integration into treatment in patients with FGFR2‐amplified gastric and colorectal cancers.

Abstract Background Oxaliplatin is a platinum derivative that has shown efficacy in advanced hepatocellular carcinoma. S-1 is an oral fluoropyrimidine that has substituted for 5-fluorouracil in many cancers. This was a multicenter, open-label, single-arm phase II trial that evaluated the efficacy of S-1 and oxaliplatin (SOX) in advanced hepatocellular carcinoma. All patients included in the present study were systemic treatment-naïve. Prior treatment with sorafenib was allowed, but other treatments were not. Methods Patients received S-1 (40 mg/m2 twice daily from day 1–14) and oxaliplatin (130 mg/m2 on day 1) every 3 weeks. The primary end point was time to progression (TTP). Secondary end points included progression-free survival, overall survival (OS), response rate, and safety profile. Results Thirty six patients with advanced hepatocellular carcinoma were included in this study. The median TTP was 3.0 months (95% confidence interval (CI), 0.75–5.25), and the median OS was 10.3 months (95% CI, 6.4–14.3). Bone metastasis was associated with poorer TTP and OS. The efficacy of SOX was unaffected by prior sorafenib or locoregional therapy. The objective response rate was 13.9%. No grade 4 toxicity or death from adverse events occurred. The most common grade 3 toxicities were neutropenia (13.9%), thrombocytopenia (13.9%), and diarrhea (8.3%). Conclusions Although this trial did not meet its primary end point, the SOX regimen showed comparable efficacy and safety to the 5-fluorouracil, leucovorin, and oxaliplatin (FOLFOX) regimen. As the SOX regimen is easier for patients, SOX may be a reasonable substitute for FOLFOX in hepatocellular carcinoma. Trial registration Clinicaltrials.gov NCT01429961. Registered 7 September 2011.

Abstract Background Capecitabine and irinotecan combination therapy (XELIRI) has been examined at various dose levels to treat metastatic colorectal cancer (mCRC). Recently, in the Association of Medical Oncology of the German Cancer Society (AIO) 0604 trial, tri-weekly XELIRI plus bevacizumab, with reduced doses of irinotecan (200 mg/m2 on day 1) and capecitabine (1600 mg/m2 on days 1–14), repeated every 3 weeks, has shown favorable tolerability and efficacy which were comparable to those of capecitabine and oxaliplatin (XELOX) plus bevacizumab. The doses of capecitabine and irinotecan in the AIO trial are considered optimal. In a phase I/II study, XELIRI plus bevacizumab (BIX) as second-line chemotherapy was well tolerated and had promising efficacy in Japanese patients. Methods The Asian XELIRI ProjecT (AXEPT) is an East Asian collaborative, open-labelled, randomized, phase III clinical trial which was designed to demonstrate the non-inferiority of XELIRI with or without bevacizumab versus standard FOLFIRI (5-fluorouracil, leucovorin, and irinotecan combination) with or without bevacizumab as second-line chemotherapy for patients with mCRC. Patients with 20 years of age or older, histologically confirmed mCRC, Eastern Cooperative Oncology Group performance status 0–2, adequate organ function, and disease progression or intolerance of the first-line regimen will be eligible. Patients will be randomized (1:1) to receive standard FOLFIRI with or without bevacizumab (5 mg/kg on day 1), repeated every 2 weeks (FOLIRI arm) or XELIRI with or without bevacizumab (7.5 mg/kg on day 1), repeated every 3 weeks (XELIRI arm). A total of 464 events were estimated as necessary to show non-inferiority with a power of 80% at a one-sided α of 0.025, requiring a target sample size of 600 patients. The 95% confidence interval (CI) upper limit of the hazard ratio was pre-specified as less than 1.3. Conclusion The Asian XELIRI ProjecT is a multinational phase III trial being conducted to provide evidence for XELIRI with or without bevacizumab as a second-line treatment option of mCRC. Trial registration ClinicalTrials.gov NCT01996306. UMIN000012263

An oral medication of a molecular targeted drug, lapatinib, is taken regularly to maintain the drug concentration within the desired therapeutic levels. To alleviate the need for such cumbersome administration schedules in several drugs, advanced drug delivery systems (DDSs), which can provide time-controlled and sustained drug release, have recently received significant attention. A biodegradable synthetic polymer, such as polycaprolactone (PCL), is usually used as a carrier material for DDSs. In this paper, lapatinib powder-entrapped, PCL microstructures were fabricated with a precise X-ray lithography-based method. In vitro experiments on HER2 positive-human gastric cancer derived NCI-N87 cells were performed to appraise the drug release characteristics of the fabricated DDSs. The in vitro results indicate that after the X-ray lithography process, the lapatinib powder is still working well and show time- and dose- dependent drug release efficiencies. The cell growth inhibition characteristics of one hundred 40-μm sized microstructures were similar to those of a 1 μM lapatinib solution for over 144 h. In conclusion, the developed lapatinib-entrapped PCL microstructures can be used in molecular targeted delivery and sustained release as effective cancer-targeted DDSs.

Colorectal cancers (CRCs) expressing programmed death ligand 1 (PD-L1) have poor prognosis. In the multicohort KEYNOTE-028 trial, the anti-PD-1 antibody pembrolizumab was evaluated in 20 PD-L1-positive advanced solid tumors. Herein, we report results for the advanced CRC cohort.Patients with advanced, treatment-resistant PD-L1-positive carcinoma of the colon or rectum were enrolled, regardless of microsatellite instability (MSI) status. Pembrolizumab 10 mg/kg was administered every 2 weeks for up to 2 years or until disease progression/unacceptable toxicity. Response was assessed every 8 weeks for the first 6 months and every 12 weeks thereafter. Primary end points were safety and overall response rate by investigator review per Response Evaluation Criteria in Solid Tumors version 1.1. Data cutoff was June 20, 2016.Of 137 patients with CRC and samples evaluable for PD-L1 expression, 33 (24%) had PD-L1-positive tumors, of which 23 were enrolled. Median follow-up was 5.3 months, and 8 patients (35%) reported treatment-related adverse events (AEs), most commonly fatigue (n = 3, 13%), stomatitis (n = 2, 9%), and asthenia (n = 2, 9%). One patient (4%) experienced grade 4 treatment-related increased blood bilirubin. No grade 3 AEs, discontinuations, or deaths were attributed to treatment. Most patients (n = 15, 65%) experienced progressive disease. One partial response occurred in a patient (4%) with MSI-high CRC.Pembrolizumab demonstrated a favorable safety profile in advanced PD-L1-positive CRC. Antitumor activity was observed in a single patient with MSI-high CRC, warranting further evaluation in this patient population. (Clinicaltrials.gov registration: NCT02054806).

Neutrophil to lymphocyte ratio (NLR) and standard uptake value (SUV) by 18F-FDG PET represent host immunity and tumor metabolic activity, respectively. We investigated NLR and maximum SUV (SUVmax) as prognostic markers in metastatic pancreatic cancer (MPC) patients who receive palliative chemotherapy.We reviewed 396 MPC patients receiving palliative chemotherapy. NLR was obtained before and after the first cycle of chemotherapy. In 118 patients with PET prior to chemotherapy, SUVmax was collected. Cut-off values were determined by ROC curve.In multivariate analysis of all patients, NLR and change in NLR after the first cycle of chemotherapy (ΔNLR) were independent prognostic factors for overall survival (OS). We scored the risk considering NLR and ΔNLR and identified 4 risk groups with different prognosis (risk score 0 vs 1 vs 2 vs 3: OS 9.7 vs 7.9 vs 5.7 vs 2.6 months, HR 1 vs 1.329 vs 2.137 vs 7.915, respectively; P

Body composition has emerged as a prognostic factor in cancer patients. We investigated whether sarcopenia at diagnosis and loss of skeletal muscle during palliative chemotherapy were associated with survival in patients with pancreatic cancer.We retrospectively reviewed the clinical outcomes of pancreatic cancer patients receiving palliative chemotherapy between 2003 and 2010. The cross-sectional area of skeletal muscle at L3 by computed tomography was analyzed with Rapidia 3D software. We defined sarcopenia as a skeletal muscle index (SMI)< 42.2 cm2/m2 (male) and < 33.9 cm2/m2 (female) using ROC curve.Among 484 patients, 103 (21.3%) patients were sarcopenic at diagnosis. Decrease in SMI during chemotherapy was observed in 156 (60.9%) male and 65 (40.6%) female patients. Decrease in body mass index (BMI) was observed in 149 patients (37.3%), with no gender difference. By multivariate analysis, sarcopenia (P< 0.001), decreasedBMI and SMI during chemotherapy (P = 0.002, P = 0.004, respectively) were poor prognostic factors for overall survival (OS). While the OS of male patients was affected with sarcopenia (P< 0.001) and decreased SMI (P = 0.001), the OS of female patients was influenced with overweight at diagnosis (P = 0.006), decreased BMI (P = 0.032) and decreased SMI (P = 0.014). Particularly, while the change of BMI during chemotherapy did not have impact on OS within the patients with maintained SMI (P = 0.750), decrease in SMI was associated with poor OS within the patients with maintained BMI (HR 1.502; P = 0.002).Sarcopenia at diagnosis and depletion of skeletal muscle, independent of BMI change, during chemotherapy were poor prognostic factors in advanced pancreatic cancer.

BACKGROUND:Regorafenib induces distinct radiological changes that represent its anti-angiogenic effect. However, clinical implication of the changes is unclear. METHODS:Tumor attenuation as measured by Hounsfield units (HU) in contrast-enhanced computed tomography (CT) and cavitary changes of lung metastases were analyzed in association with treatment outcome of metastatic colorectal cancer patients (N = 80) treated with regorafenib in a prospective study. RESULTS:141 lesions in 72 patients were analyzed with HU. After 2 cycles of regorafenib, 87.5% of patients showed decrease of HU (Median change -23.9%, range -61.5%-20.7%). Lesional attenuation change was modestly associated with metabolic changes of 18-fluoro-deoxyglucose positron emission tomography-CT (Pearson's r = 0.37, p = 0.002). Among 53 patients with lung metastases, 17 (32.1%) developed cavitary changes. There were no differences in disease control rate, progression-free survival, or overall survival according to the radiological changes. At the time of progressive disease (PD) according to RECIST 1.1, HU was lower than baseline in 86.0% (43/50) and cavitary change of lung metastasis persisted without refilling in 84.6% (11/13). CONCLUSION:Regorafenib showed prominent anti-angiogenic effect in colorectal cancer, but the changes were not associated with treatment outcome. However, the anti-angiogenic effects persisted at the time of PD, which suggests that we may need to develop new treatment strategies.

Recent advance in sequencing technology has enabled comprehensive profiling of genetic alterations in cancer. We have established a targeted sequencing platform using next-generation sequencing (NGS) technology for clinical use, which can provide mutation and copy number variation data. NGS was performed with paired-end library enriched with exons of 183 cancer-related genes. Normal and tumor tissue pairs of 60 colorectal adenocarcinomas were used to test feasibility. Somatic mutation and copy number alteration were analyzed. A total of 526 somatic non-synonymous sequence variations were found in 113 genes. Among these, 278 single nucleotide variations were 232 different somatic point mutations. 216 SNV were 79 known single nucleotide polymorphisms in the dbSNP. 32 indels were 28 different indel mutations. Median number of mutated gene per tumor was 4 (range 0-23). Copy number gain (>X2 fold) was found in 65 genes in 40 patients, whereas copy number loss (

BACKGROUND: Lapatinib plus capecitabine is an effective treatment option for trastuzumab-refractory HER2-positive metastatic breast cancer. We have investigated the correlation between quantitative measures of HER2, p95HER2, and HER3 and treatment outcomes using lapatinib and capecitabine. METHODS: Total HER2 (H2T), p95HER2 (p95), and total HER3 (H3T) expression were quantified in formalin-fixed paraffin-embedded samples using the VeraTag assays. Patients received lapatinib and capecitabine treatment following trastuzumab failure according to the Lapatinib Expanded Access Program. The association between the protein expression levels and clinical outcomes was analyzed. RESULTS: A total of 52 patients were evaluable. H2T level was significantly higher in responders (median 93.49 in partial response, 47.66 in stable disease, and 17.27 in progressive disease; p = 0.020). Longer time-to-progression (TTP) was observed in patients with high H2T [p = 0.018, median 5.2 months in high (>14.95) vs. 1.8 in low (0.605) vs. 2.2 in low (

Identification of predictive biomarkers is essential for the successful development of targeted therapy. Insulin-like growth factor 1 receptor (IGF1R) has been examined as a potential therapeutic target for various cancers. However, recent clinical trials showed that anti-IGF1R antibody and chemotherapy are not effective for treating lung cancer.In order to define biomarkers for predicting successful IGF1R targeted therapy, we evaluated the anti-proliferation effect of figitumumab (CP-751,871), a humanized anti-IGF1R antibody, against nine gastric and eight hepatocellular cancer cell lines. Out of 17 cancer cell lines, figitumumab effectively inhibited the growth of three cell lines (SNU719, HepG2, and SNU368), decreased p-AKT and p-STAT3 levels, and induced G 1 arrest in a dose-dependent manner. Interestingly, these cells showed co-overexpression and altered mobility of the IGF1R and insulin receptor (IR). Immunoprecipitaion (IP) assays and ELISA confirmed the presence of IGF1R/IR heterodimeric receptors in figitumumab-sensitive cells. Treatment with figitumumab led to the dissociation of IGF1-dependent heterodimeric receptors and inhibited tumor growth with decreased levels of heterodimeric receptors in a mouse xenograft model. We next found that both IGF1R and IR were N-linked glyosylated in figitumumab-sensitive cells. In particular, mass spectrometry showed that IGF1R had N-linked glycans at N913 in three figitumumab-sensitive cell lines. We observed that an absence of N-linked glycosylation at N913 led to a lack of membranous localization of IGF1R and figitumumab insensitivity.The data suggest that the level of N-linked glycosylated IGF1R/IR heterodimeric receptor is highly associated with sensitivity to anti-IGF1R antibody in cancer cells.

BACKGROUND: Epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) has been shown to exert a synergistic antitumor effect when combined with fluoropyrimidine. This synergy may be attributable to the downregulation of thymidylate synthase (TS), which is frequently overexpressed in fluoropyrimidine-resistant cancer cells. However, the molecular mechanism underlying the downregulation of TS has yet to be clearly elucidated. METHODOLOGY AND PRINCIPAL FINDINGS: In this study, we demonstrate that lapatinib, a dual TKI of EGFR and HER2 downregulates TS via inhibition of the nuclear translocation of EGFR and HER2. From our cDNA microarray experiments, we determined that a variety of nucleotide synthesis-related genes, including TS, were downregulated with lapatinib, and this was apparent in HER2-amplified cells. Targeted and pharmacologic inhibition assays confirmed that the dual inhibition of EGFR and HER2 is required for the more effective reduction of TS as compared to what was observed with gefitinib or trasutuzumab alone. Additionally, we determined that co-transfected EGFR and HER2 activate the TS gene promoter more profoundly than do either EGFR or HER2 alone. The translocation of EGFR and HER2 into the nucleus and the subsequent activation of the TS promoter were inhibited by lapatinib. CONCLUSIONS AND SIGNIFICANCE: These results demonstrate that lapatinib inhibits the nuclear translocation of EGFR and HER2 and downregulates TS, thus sensitizing cancer cells to fluoropyrimidine.