Colon Cancer, Version 3.2024, NCCN Clinical Practice Guidelines in Oncology.

Colorectal cancer (CRC) is the fourth most frequently diagnosed cancer and the second leading cause of cancer death in the United States. Management of disseminated metastatic CRC involves various active drugs, either in combination or as single agents. The choice of therapy is based on consideration of the goals of therapy, the type and timing of prior therapy, the mutational profile of the tumor, and the differing toxicity profiles of the constituent drugs. This manuscript summarizes the data supporting the systemic therapy options recommended for metastatic CRC in the NCCN Guidelines for Colon Cancer.

HER2-Positive Metastatic Colorectal Cancer.

OPINION STATEMENT: Targeted treatment strategies are available for human epidermal growth factor receptor 2 (HER2)-positive (amplified and/or overexpressed) metastatic colorectal cancer (mCRC), and HER2 testing is indicated in patients with mCRC. At present, standard of care first-line treatment for those with HER2-positive mCRC remains chemotherapy in combination with epidermal growth factor receptor (EGFR) inhibitors or bevacizumab, depending on RAS/BRAF mutational status and tumor sidedness. HER2-targeted agents should be considered for those with RAS/BRAF wild-type disease in subsequent-line treatment and in first-line treatment for patients not appropriate for intensive therapy. While the choice of anti-HER2 therapy is empiric given lack of head-to-head comparisons, the combination of trastuzumab plus tucatinib has received FDA accelerated approval for use in this setting and is generally the authors' preference. Trastuzumab plus lapatinib, trastuzumab plus pertuzumab, and trastuzumab deruxtecan (T-DXd) also have evidence of efficacy in this setting. As T-DXd has demonstrated activity following treatment with other HER2-targeted regimens and carries an increased risk of high-grade toxicities, the authors favor reserving it for use after progression on prior anti-HER2 therapy. HER2-targeted therapies that inhibit signal transduction appear to have limited activity in those with RAS mutations, including trastuzumab-containing regimens. However, the antibody drug conjugate T-DXd has some data showing efficacy in this setting, and the authors would consider T-DXd in subsequent-line therapy for HER2-positive, RAS-mutated mCRC. Several areas of uncertainty remain regarding how to best utilize HER2-targeted therapies in mCRC. These include the optimal sequence of anti-HER2 therapies with chemotherapy and anti-EGFR therapies, the optimal combination partners for anti-HER2 therapies, and the incorporation of predictive biomarkers to guide use of anti-HER2 therapies. Results of ongoing studies may thus alter the treatment paradigm above in the coming years.

Anal Carcinoma, Version 2.2023, NCCN Clinical Practice Guidelines in Oncology.

This discussion summarizes the NCCN Clinical Practice Guidelines for managing squamous cell anal carcinoma, which represents the most common histologic form of the disease. A multidisciplinary approach including physicians from gastroenterology, medical oncology, surgical oncology, radiation oncology, and radiology is necessary. Primary treatment of perianal cancer and anal canal cancer are similar and include chemoradiation in most cases. Follow-up clinical evaluations are recommended for all patients with anal carcinoma because additional curative-intent treatment is possible. Biopsy-proven evidence of locally recurrent or persistent disease after primary treatment may require surgical treatment. Systemic therapy is generally recommended for extrapelvic metastatic disease. Recent updates to the NCCN Guidelines for Anal Carcinoma include staging classification updates based on the 9th edition of the AJCC Staging System and updates to the systemic therapy recommendations based on new data that better define optimal treatment of patients with metastatic anal carcinoma.

ATM kinase inhibitor AZD0156 in combination with irinotecan and 5-fluorouracil in preclinical models of colorectal cancer.

BACKGROUND: AZD0156 is an oral inhibitor of ATM, a serine threonine kinase that plays a key role in DNA damage response (DDR) associated with double-strand breaks. Topoisomerase-I inhibitor irinotecan is used clinically to treat colorectal cancer (CRC), often in combination with 5-fluorouracil (5FU). AZD0156 in combination with irinotecan and 5FU was evaluated in preclinical models of CRC to determine whether low doses of AZD0156 enhance the cytotoxicity of irinotecan in chemotherapy regimens used in the clinic. METHODS: Anti-proliferative effects of single-agent AZD0156, the active metabolite of irinotecan (SN38), and combination therapy were evaluated in 12 CRC cell lines. Additional assessment with clonogenic assay, cell cycle analysis, and immunoblotting were performed in 4 selected cell lines. Four colorectal cancer patient derived xenograft (PDX) models were treated with AZD0156, irinotecan, or 5FU alone and in combination for assessment of tumor growth inhibition (TGI). Immunofluorescence was performed on tumor tissues. The DDR mutation profile was compared across in vitro and in vivo models. RESULTS: Enhanced effects on cellular proliferation and regrowth were observed with the combination of AZD0156 and SN38 in select models. In cell cycle analysis of these models, increased G2/M arrest was observed with combination treatment over either single agent. Immunoblotting results suggest an increase in DDR associated with irinotecan therapy, with a reduced effect noted when combined with AZD0156, which is more pronounced in some models. Increased TGI was observed with the combination of AZD0156 and irinotecan as compared to single-agent therapy in some PDX models. The DDR mutation profile was variable across models. CONCLUSIONS: AZD0156 and irinotecan provide a rational and active combination in preclinical colorectal cancer models. Variability across in vivo and in vitro results may be related to the variable DDR mutation profiles of the models evaluated. Further understanding of the implications of individual DDR mutation profiles may help better identify patients more likely to benefit from treatment with the combination of AZD0156 and irinotecan in the clinical setting.

Rectal Cancer, Version 2.2022, NCCN Clinical Practice Guidelines in Oncology.

This selection from the NCCN Guidelines for Rectal Cancer focuses on management of malignant polyps and resectable nonmetastatic rectal cancer because important updates have been made to these guidelines. These recent updates include redrawing the algorithms for stage II and III disease to reflect new data supporting the increasingly prominent role of total neoadjuvant therapy, expanded recommendations for short-course radiation therapy techniques, and new recommendations for a "watch-and-wait" nonoperative management technique for patients with cancer that shows a complete response to neoadjuvant therapy. The complete version of the NCCN Guidelines for Rectal Cancer, available online at NCCN.org, covers additional topics including risk assessment, pathology and staging, management of metastatic disease, posttreatment surveillance, treatment of recurrent disease, and survivorship.

Evorpacept alone and in combination with pembrolizumab or trastuzumab in patients with advanced solid tumours (ASPEN-01): a first-in-human, open-label, multicentre, phase 1 dose-escalation and dose-expansion study.

BACKGROUND: Both innate and adaptive immune responses are important components of anticancer immunity. The CD47-SIRPα interaction could represent an important pathway used by tumour cells to evade immune surveillance. We aimed to evaluate the safety, pharmacokinetics, pharmacodynamics, and anticancer activity of evorpacept (also known as ALX148), a high-affinity CD47-blocking protein with an inactive IgG Fc region in patients with solid tumours. METHODS: We did a first-in-human, open-label, multicentre, phase 1 dose-escalation and dose-expansion study at nine hospitals and one clinic in the USA and Korea. Eligible patients for the dose-escalation and safety lead-in phases were aged 18 years or older with histological or cytological diagnosis of advanced or metastatic solid tumours with no available standard therapy, measurable or unmeasurable disease according to the Response Evaluation Criteria in Solid Tumors version 1.1, and an Eastern Cooperative Oncology Group performance status score of 0 or 1. In the dose-escalation phase, which used a 3 + 3 design, patients received intravenous evorpacept at either 0·3, 1, 3, or 10 mg/kg once per week in 21-day cycles, or 30 mg/kg once every other week in 28-day cycles. In the safety lead-in phase, patients were given the maximum tolerable dose of evorpacept from the dose-escalation phase plus either intravenous pembrolizumab (200 mg administered once every 3 weeks) or intravenous trastuzumab (8 mg/kg loading dose followed by 6 mg/kg once every 3 weeks). In the dose-expansion phase, additional patients aged 18 years or older with second-line or later-line advanced malignancies were enrolled into three parallel cohorts: those with head and neck squamous cell carcinoma (HNSCC) and those with non-small-cell lung cancer (NSCLC) were given the maximum tolerated dose of evorpacept plus intravenous pembrolizumab (200 mg administered once every 3 weeks), and patients with HER2-positive gastric or gastroesophageal junction cancer were given the maximum tolerated dose of evorpacept plus intravenous trastuzumab (8 mg/kg loading dose followed by 6 mg/kg once every 3 weeks) until disease progression, voluntary withdrawal from the study, or unacceptable toxicity. The primary endpoint was the maximum tolerated dose of evorpacept administered as a single agent and in combination with pembrolizumab or trastuzumab, measured by the occurrence of dose-limiting toxicities during the first cycle, and was assessed in all patients who had received at least one dose of evorpacept. Secondary outcomes included the safety, tolerability, and antitumour activity of evorpacept, alone or in combination with pembrolizumab or trastuzumab. The primary outcome, safety, and tolerability were assessed in all patients who had received at least one dose of evorpacept, and antitumour activity was assessed in those who recieved at least one dose of study treatment and underwent at least one post-baseline tumor assessment. This trial is registered with ClinicalTrials.gov, NCT03013218. FINDINGS: Between March 6, 2017, and Feb 21, 2019, 110 patients received single-agent evorpacept (n=28), evorpacept plus pembrolizumab (n=52), or evorpacept plus trastuzumab (n=30), and were included in the safety analysis. Median follow-up was 29·1 months (95% CI not calculable [NC]-NC) in the single-agent cohort, 27·0 months (25·1-28·8) in the evorpacept plus pembrolizumab cohort, and 32·7 months (27·0-32·7) in the evorpacept plus trastuzumab cohort. Two (7%) dose-limiting toxicities in the first cycle were reported in patients who received single-agent evorpacept; neutropenia with an associated infection in one patient with gastroesophageal junction cancer who received 3 mg/kg once per week, and thrombocytopenia with associated bleeding in one patient with pancreatic cancer who received 30 mg/kg once every other week. No maximum tolerated dose was reached; the maximum administered doses were 10 mg/kg once per week or 30 mg/kg once every other week. The 10 mg/kg once per week dose was used in the expansion cohorts in combination with pembrolizumab or trastuzumab. The most common grade 3 or worse treatment-related adverse events were thrombocytopenia with single-agent evorpacept (two [7%] patients) and evorpacept plus pembrolizumab (two [4%]), and thrombocytopenia (two [7%]) and neutropenia (two [7%]) with evorpacept plus trastuzumab. In patients who received single-agent evorpacept, four treatment-related serious adverse events were reported. Five serious treatment-related adverse events related to evorpacept plus pembrolizumab were reported, and one serious adverse event related to evorpacept plus trastuzumab was reported. In response-evaluable patients in the dose-escalation phase (n=15) receiving single-agent evorpacept once per week, four (27%) had a best overall response of stable disease (two received 0·3 mg/kg, one received 3 mg/kg, and one received 10 mg/kg); in the 11 patients who received single-agent evorpacept at the highest dose of 30 mg/kg once every other week, two (18%) had stable disease. In the dose-expansion cohort, overall responses were recorded in four (20·0%; 95% CI 5·7-43·7) of 20 patients with HNSCC who received evorpacept plus pembrolizumab, in one (5·0%; 0·1-24·9) of 20 patients with NSCLC who received evorpacept plus pembrolizumab, and in four (21·1%; 6·1-45·6) of 19 patients with gastric or gastroesophageal junction cancer who received evorpacept plus trastuzumab. INTERPRETATION: The safety findings support the use of evorpacept in combination with pembrolizumab or trastuzumab for patients with advanced solid tumours. Preliminary antitumour activity results support future investigation of evorpacept combined with pembrolizumab or trastuzumab in patients with HNSCC, gastric or gastroesophageal junction cancer, and NSCLC. FUNDING: ALX Oncology.

Response to radiotherapy in pancreatic ductal adenocarcinoma is enhanced by inhibition of myeloid-derived suppressor cells using STAT3 anti-sense oligonucleotide.

Pancreatic ductal adenocarcinoma (PDAC) has a heterogeneous tumor microenvironment (TME) comprised of myeloid-derived suppressor cells (MDSCs), tumor-associated macrophages, neutrophils, regulatory T cells, and myofibroblasts. The precise mechanisms that regulate the composition of the TME and how they contribute to radiotherapy (RT) response remain poorly understood. In this study, we analyze changes in immune cell populations and circulating chemokines in patient samples and animal models of pancreatic cancer to characterize the immune response to radiotherapy. Further, we identify STAT3 as a key mediator of immunosuppression post-RT. We found granulocytic MDSCs (G-MDSCs) and neutrophils to be increased in response to RT in murine and human PDAC samples. We also found that RT-induced STAT3 phosphorylation correlated with increased MDSC infiltration and proliferation. Targeting STAT3 using an anti-sense oligonucleotide in combination with RT circumvented RT-induced MDSC infiltration, enhanced the proportion of effector T cells, and improved response to RT. In addition, STAT3 inhibition contributed to the remodeling of the PDAC extracellular matrix when combined with RT, resulting in decreased collagen deposition and fibrotic tissue formation. Collectively, our data provide evidence that targeting STAT3 in combination with RT can mitigate the pro-tumorigenic effects of RT and improve tumor response.

Colon Cancer, Version 2.2021, NCCN Clinical Practice Guidelines in Oncology.

This selection from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Colon Cancer focuses on systemic therapy options for the treatment of metastatic colorectal cancer (mCRC), because important updates have recently been made to this section. These updates include recommendations for first-line use of checkpoint inhibitors for mCRC, that is deficient mismatch repair/microsatellite instability-high, recommendations related to the use of biosimilars, and expanded recommendations for biomarker testing. The systemic therapy recommendations now include targeted therapy options for patients with mCRC that is HER2-amplified, or BRAF V600E mutation-positive. Treatment and management of nonmetastatic or resectable/ablatable metastatic disease are discussed in the complete version of the NCCN Guidelines for Colon Cancer available at NCCN.org. Additional topics covered in the complete version include risk assessment, staging, pathology, posttreatment surveillance, and survivorship.

Predicting pregnancy status from mid-infrared spectroscopy in dairy cow milk using deep learning.

Accurately identifying pregnancy status is imperative for a profitable dairy enterprise. Mid-infrared (MIR) spectroscopy is routinely used to determine fat and protein concentrations in milk samples. Mid-infrared spectra have successfully been used to predict other economically important traits, including fatty acid content, mineral content, body energy status, lactoferrin, feed intake, and methane emissions. Machine learning has been used in a variety of fields to find patterns in vast quantities of data. This study aims to use deep learning, a sub-branch of machine learning, to establish pregnancy status from routinely collected milk MIR spectral data. Milk spectral data were obtained from National Milk Records (Chippenham, UK), who collect large volumes of data continuously on a monthly basis. Two approaches were followed: using genetic algorithms for feature selection and network design (model 1), and transfer learning with a pretrained DenseNet model (model 2). Feature selection in model 1 showed that the number of wave points in MIR data could be reduced from 1,060 to 196 wave points. The trained model converged after 162 epochs with validation accuracy and loss of 0.89 and 0.18, respectively. Although the accuracy was sufficiently high, the loss (in terms of predicting only 2 labels) was considered too high and suggested that the model would not be robust enough to apply to industry. Model 2 was trained in 2 stages of 100 epochs each with spectral data converted to gray-scale images and resulted in accuracy and loss of 0.97 and 0.08, respectively. Inspection on inference data showed prediction sensitivity of 0.89, specificity of 0.86, and prediction accuracy of 0.88. Results indicate that milk MIR data contains features relating to pregnancy status and the underlying metabolic changes in dairy cows, and such features can be identified by means of deep learning. Prediction equations from trained models can be used to alert farmers of nonviable pregnancies as well as to verify conception dates.

Impact of neoadjuvant chemotherapy and stereotactic body radiation therapy (SBRT) on R0 resection rate for borderline resectable and locally advanced pancreatic cancer.

BACKGROUND: The role of neoadjuvant stereotactic body radiation therapy (SBRT) in patients with borderline resectable pancreas cancer (BRPC) and locally advanced pancreas cancer (LAPC) remains controversial. METHODS: We retrospectively evaluated BRPC and LAPC patients treated at our institution who underwent 2-3 months of chemotherapy followed by SBRT to a dose of 30-33 Gy. Overall survival (OS) and recurrence-free survival (RFS) were estimated and compared by Kaplan-Meier and log-rank methods. RESULTS: We identified 103 (85 BRPC and 18 LAPC) patients treated per our neoadjuvant paradigm between 2011 and 2018, with resectability based on NCCN definitions. Median follow up was 25 months. Of patients completing neoadjuvant therapy, 73 (71%) underwent definitive resection. Seventy-one (97%) patients with definitively resected tumors had R0 resection and 5 (7%) had a complete pathologic response CR to neoadjuvant therapy. The median overall survival (OS) of the cohort was 24 months. Those with a complete or marked pathologic response had significantly better OS than those with a moderate response (41 vs 24 months, p < 0.02) and patients unable to undergo definitive surgery (17 months, p < 0.0003). Six resected patients experienced grade ≥3 surgical complications. CONCLUSIONS: Neoadjuvant chemotherapy and SBRT are associated with promising pathologic response rates and R0 resection rates, with acceptable perioperative morbidity.

Bitter melon juice intake with gemcitabine intervention circumvents resistance to gemcitabine in pancreatic patient-derived xenograft tumors.

Chemoresistance to gemcitabine (GEM)-a frontline chemotherapeutic, resulting from its dysfunctional uptake and metabolism in cancer cells, is a major contributing factor for failed therapy in pancreatic cancer (PanC) patients. Therefore, there is an urgent need for agents that could reverse GEM resistance and allow continued chemosensitivity to the drug. We employed natural nontoxic agent (with anti-PanC potential) bitter melon juice (BMJ) and GEM to examine their combinatorial benefits against tumorigenesis of PanC patient-derived xenograft (PDX)-pancreatic ductal adenocarcinomas explants PDX272 (wild-type KRAS), PDX271 (mutant KRAS and SMAD4), and PDX266 (mutant KRAS). Anti-PanC efficacy of single agents vs combination in the three tumor explants, both at the end of active dosing regimen and following a drug-washout phase were compared. In animal studies, GEM alone treatment significantly inhibited PDX tumor growth, but effects were not sustained, as GEM-treated tumors exhibited regrowth posttreatment termination. However, combination-regimen displayed enhanced and sustained efficacy. Mechanistic assessments revealed that overcoming GEM resistance by coadministration with BMJ was possibly due to modulation of GEM transport/metabolism pathway molecules (ribonucleotide reductase regulatory subunit M1, human equilibrative nucleoside transporter 1, and deoxycytidine kinase). Study outcomes, highlighting significantly higher and sustained efficacy of GEM in combination with BMJ, make a compelling case for a clinical trial in PanC patients, wherein BMJ could be combined with GEM to target and overcome GEM resistance. In addition, given their specific effectiveness against KRAS-mutant tumors, this combination could be potentially beneficial to a broader PanC patient population.

A phase 1b dose escalation study of Wnt pathway inhibitor vantictumab in combination with nab-paclitaxel and gemcitabine in patients with previously untreated metastatic pancreatic cancer.

Vantictumab is a fully human monoclonal antibody that inhibits Wnt pathway signaling through binding FZD1, 2, 5, 7, and 8 receptors. This phase Ib study evaluated vantictumab in combination with nab-paclitaxel and gemcitabine in patients with untreated metastatic pancreatic adenocarcinoma. Patients received vantictumab at escalating doses in combination with standard dosing of nab-paclitaxel and gemcitabine according to a 3 + 3 design. A total of 31 patients were treated in 5 dosing cohorts. Fragility fractures attributed to vantictumab occurred in 2 patients in Cohort 2 (7 mg/kg every 2 weeks), and this maximum administered dose (MAD) on study was considered unsafe. The dosing schedule was revised to every 4 weeks for Cohorts 3 through 5, with additional bone safety parameters added. Sequential dosing of vantictumab followed by nab-paclitaxel and gemcitabine was also explored. No fragility fractures attributed to vantictumab occurred in these cohorts; pathologic fracture not attributed to vantictumab was documented in 2 patients. The study was ultimately terminated due to concerns around bone-related safety, and thus the maximum tolerated dose (MTD) of the combination was not determined. The MAD of vantictumab according to the revised dosing schedule was 5 mg/kg (n = 16).

NCCN Guidelines Insights: Rectal Cancer, Version 6.2020.

The NCCN Guidelines for Rectal Cancer provide recommendations for the diagnosis, evaluation, treatment, and follow-up of patients with rectal cancer. These NCCN Guidelines Insights summarize the panel discussion behind recent important updates to the guidelines. These updates include clarifying the definition of rectum and differentiating the rectum from the sigmoid colon; the total neoadjuvant therapy approach for localized rectal cancer; and biomarker-targeted therapy for metastatic colorectal cancer, with a focus on new treatment options for patients with BRAF V600E- or HER2 amplification-positive disease.

Predicting bovine tuberculosis status of dairy cows from mid-infrared spectral data of milk using deep learning.

Bovine tuberculosis (bTB) is a zoonotic disease in cattle that is transmissible to humans, distributed worldwide, and considered endemic throughout much of England and Wales. Mid-infrared (MIR) analysis of milk is used routinely to predict fat and protein concentration, and is also a robust predictor of several other economically important traits including individual fatty acids and body energy. This study predicted bTB status of UK dairy cows using their MIR spectral profiles collected as part of routine milk recording. Bovine tuberculosis data were collected as part of the national bTB testing program for Scotland, England, and Wales; these data provided information from over 40,500 bTB herd breakdowns. Corresponding individual cow life-history data were also available and provided information on births, movements, and deaths of all cows in the study. Data relating to single intradermal comparative cervical tuberculin (SICCT) skin-test results, culture, slaughter status, and presence of lesions were combined to create a binary bTB phenotype labeled 0 to represent nonresponders (i.e., healthy cows) and 1 to represent responders (i.e., bTB-affected cows). Contemporaneous individual milk MIR spectral data were collected as part of monthly routine milk recording and matched to bTB status of individual animals on the single intradermal comparative cervical tuberculin test date (±15 d). Deep learning, a sub-branch of machine learning, was used to train artificial neural networks and develop a prediction pipeline for subsequent use in national herds as part of routine milk recording. Spectra were first converted to 53 × 20-pixel PNG images, then used to train a deep convolutional neural network. Deep convolutional neural networks resulted in a bTB prediction accuracy (i.e., the number of correct predictions divided by the total number of predictions) of 71% after training for 278 epochs. This was accompanied by both a low validation loss (0.71) and moderate sensitivity and specificity (0.79 and 0.65, respectively). To balance data in each class, additional training data were synthesized using the synthetic minority over sampling technique. Accuracy was further increased to 95% (after 295 epochs), with corresponding validation loss minimized (0.26), when synthesized data were included during training of the network. Sensitivity and specificity also saw a 1.22- and 1.45-fold increase to 0.96 and 0.94, respectively, when synthesized data were included during training. We believe this study to be the first of its kind to predict bTB status from milk MIR spectral data. We also believe it to be the first study to use milk MIR spectral data to predict a disease phenotype, and posit that the automated prediction of bTB status at routine milk recording could provide farmers with a robust tool that enables them to make early management decisions on potential reactor cows, and thus help slow the spread of bTB.

NCCN Guidelines Updates: Management of Metastatic Colorectal Cancer.

In the last year, several impactful updates have been added to the NCCN Guidelines for Colorectal Cancer (CRC) for the management of metastatic disease, including additional options for BRAF-mutated advanced CRC and the inclusion of combination immunotherapy (PD-1 and CTLA-4) for deficient mismatch repair/microsatellite instability (MSI)-high advanced CRC. According to Dr. Wells A. Messersmith, targeted therapies (ie, VEGFR, EGFR, multitargeted tyrosine kinase inhibitors) play an important role in CRC management, but none of them have been successful in the adjuvant setting (although checkpoint inhibition is now being tested in MSI-high stage III CRC). Reliable predictive biomarkers for most agents are still greatly lacking, highlighting the importance of investing in CRC biomarker studies.

Small Bowel Adenocarcinoma, Version 1.2020, NCCN Clinical Practice Guidelines in Oncology.

Small bowel adenocarcinoma (SBA) is a rare malignancy of the gastrointestinal tract that has increased in incidence across recent years. Often diagnosed at an advanced stage, outcomes for SBA are worse on average than for other related malignancies, including colorectal cancer. Due to the rarity of this disease, few studies have been done to direct optimal treatment, although recent data have shown that SBA responds to treatment differently than colorectal cancer, necessitating a separate approach to treatment. The NCCN Guidelines for Small Bowel Adenocarcinoma were created to establish an evidence-based standard of care for patients with SBA. These guidelines provide recommendations on the workup of suspected SBA, primary treatment options, adjuvant treatment, surveillance, and systemic therapy for metastatic disease. Additionally, principles of imaging and endoscopy, pathologic review, surgery, radiation therapy, and survivorship are described.

OsmiR528 Enhances Cold Stress Tolerance by Repressing Expression of Stress Response-related Transcription Factor Genes in Plant Cells.

BACKGROUND: MicroRNAs participate in many molecular mechanisms and signaling trans-duction pathways that are associated with plant stress tolerance by repressing expression of their target genes. However, how microRNAs enhance tolerance to low temperature stress in plant cells remains elusive. OBJECTIVE: In this investigation, we demonstrated that overexpression of the rice microRNA528 (Os-miR528) increases cell viability, growth rate, antioxidants content, ascorbate peroxidase (APOX) activi-ty, and superoxide dismutase (SOD) activity and decreases ion leakage rate and thiobarbituric acid reac-tive substances (TBARS) under low temperature stress in Arabidopsis (Arabidopsis thaliana), pine (Pi-nus elliottii), and rice (Oryza sativa). METHODS: To investigate the potential mechanism of OsmiR528 in increasing cold stress tolerance, we examined expression of stress-associated MYB transcription factors OsGAMYB-like1, OsMYBS3, OsMYB4, OsMYB3R-2, OsMYB5, OsMYB59, OsMYB30, OsMYB1R, and OsMYB20 in rice cells by qRT-PCR. RESULTS: Our experiments demonstrated that OsmiR528 decreases expression of transcription factor OsMYB30 by targeting a F-box domain containing protein gene (Os06g06050), which is a positive regulator of OsMYB30. In OsmiR528 transgenic rice, reduced OsMYB30 expression results in in-creased expression of BMY genes OsBMY2, OsBMY6, and OsBMY10. The transcript levels of the OsBMY2, OsBMY6, and OsBMY10 were elevated by OsMYB30 knockdown, but decreased by Os-MYB30 overexpression in OsmiR528 transgenic cell lines, suggesting that OsmiR528 increases low temperature tolerance by modulating expression of stress response-related transcription factor. CONCLUSION: Our experiments provide novel information in increasing our understanding in molecular mechanisms of microRNAs-associated low temperature tolerance and are valuable in plant molecular breeding from monocotyledonous, dicotyledonous, and gymnosperm plants.

A Phase I Dose-Escalation Study of Linsitinib (OSI-906), a Small-Molecule Dual Insulin-Like Growth Factor-1 Receptor/Insulin Receptor Kinase Inhibitor, in Combination with Irinotecan in Patients with Advanced Cancer.

LESSONS LEARNED: The maximum tolerated dose of the combination of linsitinib and irinotecan is linsitinib 450 mg daily on days 1-3 every 7 days and irinotecan 125 mg/m2 days 1 and 8 of a 21-day cycle.The adverse effects associated with the combination are not significantly increased beyond what is expected of each drug as a single agent.Multiple negative trials of insulin-like growth factor-1 receptor inhibitors performed in unselected patient populations led to the early discontinuation of linistinib development and this trial.Earlier integration of assessment of potential predictive biomarkers into clinical trials, as was planned in this study, is vital to the development of targeted therapies in oncology. BACKGROUND: This phase I dose-escalation study was designed to evaluate the safety and tolerability of the combination of irinotecan and insulin-like growth factor-1 receptor (IGF-1R) inhibitor linsitinib in patients with advanced cancer refractory to standard therapy. METHODS: Dose escalation in three specified dose levels was performed according to a standard 3 + 3 design. Dose levels were as follows: (a) linsitinib 400 mg and irinotecan 100 mg/m2, (b) linsitinib 450 mg and irinotecan 100 mg/m2, and (c) linsitinib 450 mg and irinotecan 125 mg/m2. Linisitinib was administered once daily on days 1-3, 8-10, and 15-17, and irinotecan on days 1 and 8. Assessment of a candidate predictive biomarker was planned in all patients, with further evaluation in an expansion cohort of advanced colorectal cancer. RESULTS: A total of 17 patients were treated, with 1 patient in both cohort 2 and 3 experiencing dose-limiting toxicity. Linsitinib 450 mg and irinotecan 125 mg/m2 was the maximum tolerated dose. Sixteen (94%) patients experienced at least one treatment-related adverse event. Neutropenia was the only grade >3 toxicity (4%). No significant hyperglycemia or QT interval prolongation was noted. No objective responses were observed; 47% (n = 8) had stable disease with median duration of 5.25 months. CONCLUSION: Although the combination was determined safe, the study was halted due to termination of linsitinib development, and biomarker testing was not performed.

A phase 1, dose-escalation study of PF-06664178, an anti-Trop-2/Aur0101 antibody-drug conjugate in patients with advanced or metastatic solid tumors.

Purpose and Methods Trop-2 is a glycoprotein over-expressed in many solid tumors but at low levels in normal human tissue, providing a potential therapeutic target. We conducted a phase 1 dose-finding study of PF-06664178, an antibody-drug conjugate that targets Trop-2 for the selective delivery of the cytotoxic payload Aur0101. The primary objective was to determine the maximum tolerated dose and recommended phase 2 dose. Secondary objectives included further characterization of the safety profile, pharmacokinetics and antitumor activity. Eligible patients were enrolled and received multiple escalating doses of PF-06664178 in an open-label and unblinded manner based on a modified continual reassessment method. Results Thirty-one patients with advanced or metastatic solid tumors were treated with escalating doses of PF-06664178 given intravenously every 21 days. Doses explored ranged from 0.15 mg/kg to 4.8 mg/kg. Seven patients experienced at least one dose limiting toxicity (DLT), either neutropenia or rash. Doses of 3.60 mg/kg, 4.2 mg/kg and 4.8 mg/kg were considered intolerable due to DLTs in skin rash, mucosa and neutropenia. Best overall response was stable disease in 11 patients (37.9%). None of the patients had a partial or complete response. Systemic exposure of PF-06664178 increased in a dose-related manner. Serum concentrations of free Aur0101 were substantially lower than those of PF-06664178 and total antibody. No correlation of Trop-2 expression and objective response was observed, although Trop-2 overexpression was not required for study entry. The intermediate dose of 2.4 mg/kg appeared to be the highest tolerated dose, but this was not fully explored as the study was terminated early due to excess toxicity. Conclusion PF-06664178 showed toxicity at high dose levels with modest antitumor activity. Neutropenia, skin rash and mucosal inflammation were dose limiting toxicities. Findings from this study may potentially aid in future antibody drug conjugate design and trials.

Antitumor activity of the polo-like kinase inhibitor, TAK-960, against preclinical models of colorectal cancer.

BACKGROUND: Polo-like kinase 1 (Plk1) is a serine/threonine kinase that is a key regulator of multiple stages of mitotic progression. Plk1 is upregulated in many tumor types including colorectal cancer (CRC) and portends a poor prognosis. TAK-960 is an ATP-competitive Plk1 inhibitor that has demonstrated efficacy across a broad range of cancer cell lines, including CRC. In this study, we investigated the activity of TAK-960 against a large collection of CRC models including 55 cell lines and 18 patient-derived xenografts. METHODS: Fifty-five CRC cell lines and 18 PDX models were exposed to TAK-960 and evaluated for proliferation (IC50) and Tumor Growth Inhibition Index, respectively. Additionally, 2 KRAS wild type and 2 KRAS mutant PDX models were treated with TAK-960 as single agent or in combination with cetuximab or irinotecan. TAK-960 mechanism of action was elucidated through immunoblotting and cell cycle analysis. RESULTS: CRC cell lines demonstrated a variable anti-proliferative response to TAK-960 with IC50 values ranging from 0.001 to > 0.75 µmol/L. Anti-proliferative effects were sustained after removal of drug. Following TAK-960 treatment a highly variable accumulation of mitotic (indicating cell cycle arrest) and apoptotic markers was observed. Cell cycle analysis demonstrated that TAK-960 treatment induced G2/M arrest and polyploidy. Six out of the eighteen PDX models responded to single agent TAK-960 therapy (TGII< 20). The addition of TAK-960 to standard of care chemotherapy resulted in largely additive antitumor effects. CONCLUSION: TAK-960 is an active anti-proliferative agent against CRC cell lines and PDX models. Collectively, these data suggest that TAK-960 may be of therapeutic benefit alone or in combination with other agents, although future work should focus on the development of predictive biomarkers and hypothesis-driven rational combinations.