Preclinical SPECT and SPECT-CT in Oncology

Molecular imaging enables both spatial and temporal understanding of the complex biologic systems underlying carcinogenesis and malignant spread. Single-photon emission tomography (SPECT) is a versatile nuclear imaging-based technique with ideal properties to study these processes in vivo in small animal models, as well as to identify potential drug candidates and characterize their antitumor action and potential adverse effects. Small animal SPECT and SPECT-CT (single-photon emission tomography combined with computer tomography) systems continue to evolve, as do the numerous SPECT radiopharmaceutical agents, allowing unprecedented sensitivity and quantitative molecular imaging capabilities. Several of these advances, their specific applications in oncology as well as new areas of exploration are highlighted in this chapter.

Surgical treatment of ovarian cancer liver metastasis

In addition to hepatocellular carcinoma, metastatic liver cancer (MLC) is another focus of hepatic surgeon. Good outcome of patients with liver metastasis (LM) from colorectal cancer or neuroendocrine tumor have been achieved. Ovarian cancer liver metastasis (OCLM) has its unique oncological characteristics and a variety of metastasis patterns, which brings a challenge to hepatic surgeon. Hepatic surgeons hold different views and techniques from gynecologists, which makes differences in the evaluation and treatment of the disease. We reviewed recent studies and, in combination with our own clinical experience, attempted to introduce the progress of surgical treatment of liver metastases from OC. In our experience, both preoperative imaging and surgical procedures are based on the assurance of R0 resection. R0 cytoreductive surgery (CRS) is the most favorable determinant for the prognosis of OC patients, and R0 liver resection (LR) is a component of R0 CRS. Gynecologists and hepatic surgeons should do their own preoperative and intraoperative evaluation for the extrahepatic and intrahepatic metastasis respectively. During the operation, regardless of the miliary nodules dissemination between the right hemidiaphragm and liver capsule, liver parenchymal infiltration (LPI) or liver parenchymal metastasis (LPM), 1-2 cm resection margin should be emphasized. For patients with liver portal lymph node metastasis (LPLNM), hepatic portal skeletonization should be performed, rather than portal lymph node dissection. The operation should be as radical as possible to ensure the patients to achieve good prognosis.

Curcumin and Resveratrol as Promising Natural Remedies with Nanomedicine Approach for the Effective Treatment of Triple Negative Breast Cancer

Researchers have made considerable progress in last few decades in understanding mechanisms underlying pathogenesis of breast cancer, its phenotypes, its molecular and genetic changes, its physiology, and its prognosis. This has allowed us to identify specific targets and design appropriate chemical entities for effective treatment of most breast cancer phenotypes, resulting in increased patient survivability. Unfortunately, these strategies have been largely ineffective in the treatment of triple negative breast cancer (TNBC). Hormonal receptors lacking render the conventional breast cancer drugs redundant, forcing scientists to identify novel targets for treatment of TNBC. Two natural compounds, curcumin and resveratrol, have been widely reported to have anticancer properties. In vitro and in vivo studies show promising results, though their effectiveness in clinical settings has been less than satisfactory, owing to their feeble pharmacokinetics. Here we discuss these naturally occurring compounds, their mechanism as anticancer agents, their shortcomings in translational research, and possible methodology to improve their pharmacokinetics/pharmacodynamics with advanced drug delivery systems.

Preoperative carboplatin-paclitaxel-bevacizumab in triple-negative breast cancer: final results of the phase II Ca.Pa.Be study

PURPOSE

The phase II Ca.Pa.Be trial evaluated preoperative carboplatin-paclitaxel in combination with bevacizumab in triple-negative breast cancer patients with previously untreated stage II-III disease. The primary aim was the assessment of the rate of pathologic complete response (pCR). Secondary aims included safety, breast-conserving surgery rate, and early response assessment with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).

METHODS

Patients with hormone receptor-negative, HER-2-negative stage II-III breast cancer were eligible. Treatment included paclitaxel 80 mg/mq + carboplatin area under the curve (AUC) 2 on days 1, 8, and 15, combined with bevacizumab 10 mg/kg on days 1 and 15 each 28 days, for 5 courses. At baseline, patients underwent breast DCE-MRI, followed by a single dose of bevacizumab 5 mg/kg (day -6). DCE-MRI was repeated before the initiation of chemotherapy.

RESULTS

Forty-four patients were enrolled. Forty-three patients underwent surgery, and 22 (50 %) received breast-conserving surgery (conversion rate from mastectomy indication at baseline, 34.4 %). A pCR in breast and axillary lymph nodes occurred in 22 patients (50 %). Bevacizumab-associated adverse events (AEs) were mild: G1-2 hypertension and bleeding occurred in 6 (13.6 %) and 12 (27 %) patients, respectively. No G4 nonhematologic AEs were recorded. More frequent G3 AEs were liver function test abnormalities (6.8 %), and diarrhea and fatigue (4.5 % each). The only G3-4 hematologic toxicity was neutropenia (G3, 25 %; G4, 9 %). Early assessed DCE-MRI response parameters failed to predict pCR.

CONCLUSIONS

The neoadjuvant anthracycline-free combination of weekly paclitaxel and carboplatin plus bevacizumab is active and safe in triple-negative breast cancer, and the rate of pCR is comparable to that observed with more intensive carboplatin- and bevacizumab-containing regimens. Further investigation is warranted.

BRCA1 and Oxidative Stress

The breast cancer susceptibility gene 1 (BRCA1) has been well established as a tumor suppressor and functions primarily by maintaining genome integrity. Genome stability is compromised when cells are exposed to oxidative stress. Increasing evidence suggests that BRCA1 regulates oxidative stress and this may be another mechanism in preventing carcinogenesis in normal cells. Oxidative stress caused by reactive oxygen species (ROS) is implicated in carcinogenesis and is used strategically to treat human cancer. Thus, it is essential to understand the function of BRCA1 in oxidative stress regulation. In this review, we briefly summarize BRCA1's many binding partners and mechanisms, and discuss data supporting the function of BRCA1 in oxidative stress regulation. Finally, we consider its significance in prevention and/or treatment of BRCA1-related cancers.

Herceptin resistance database for understanding mechanism of resistance in breast cancer patients

Monoclonal antibody Trastuzumab/Herceptin is considered as frontline therapy for Her2-positive breast cancer patients. However, it is not effective against several patients due to acquired or de novo resistance. In last one decade, several assays have been performed to understand the mechanism of Herceptin resistance with/without supplementary drugs. This manuscript describes a database HerceptinR, developed for understanding the mechanism of resistance at genetic level. HerceptinR maintains information about 2500 assays performed against various breast cancer cell lines (BCCs), for improving sensitivity of Herceptin with or without supplementary drugs. In order to understand Herceptin resistance at genetic level, we integrated genomic data of BCCs that include expression, mutations and copy number variations in different cell lines. HerceptinR will play a vital role in i) designing biomarkers to identify patients eligible for Herceptin treatment and ii) identification of appropriate supplementary drug for a particular patient. HerceptinR is available at http://crdd.osdd.net/raghava/herceptinr/.

Relapsed triple-negative breast cancer: challenges and treatment strategies

Triple negative breast cancer (TNBC) is the most lethal form of breast cancer. Treatment options for advanced disease are limited, with a median survival from the time of developing metastases rarely exceeding 1 year. TNBC is heterogeneous, and harbours several molecular alterations. Unfortunately, up to now, clinical trials combining targeted agents and chemotherapy have failed to show substantial survival improvement; therefore, chemotherapy remains the backbone of treatment. No major advances have been made in the field of cytotoxic treatments, and hopefully ongoing trials will contribute to a more precise definition of the role of platinum salts in sporadic and BRCA-mutated TNBC. Moreover, recent gene expression data suggest that TNBC can be further segmented into smaller subgroups, characterized by different activated pathways, which may therefore warrant different targeted treatments. The lack of efficacy that has been observed for the majority of targeted agents in TNBC so far may derive from the inclusion of unselected TNBC patient populations, not enriched for patients presenting an alteration in the target. Therefore, one of the major challenges in the future is to integrate biological data into clinical trials to obtain the highest efficacy from promising targeted treatments such as anti-angiogenetic agents, poly (ADP-ribose) polymerase-1 (PARP), epidermal growth factor receptor, fibroblast growth factor receptor, androgen receptor and phosphoinositide 3-kinase/mammalian target of rapamycin (PI3K/mTOR) inhibitors.

The functional role of Notch signaling in triple-negative breast cancer

The term "triple-negative breast cancer" (TNBC) is a heterogeneous subtype of breast cancer. Unfortunately, due to the lack of expression of hormone receptors and human epidermal growth factor receptor-2, therefore the lack of US Food and Drug Administration-approved targeted therapies, TNBC has the worst prognosis of all subtypes of breast cancer. Notch signaling has emerged as a pro-oncogene in several human malignancies and has particularly been associated with the triple-negative subtype of breast cancer. This chapter explores the role of Notch signaling in triple negative and other subtypes of breast cancer, the relationship of Notch with other breast cancer biomarkers, prognostic indicators associated with Notch, and potential therapeutic strategies targeting Notch inhibition. Hopefully, better understanding of this signaling pathway in the future will lead to optimal molecular therapeutic treatments for TNBC patients, improving their quality of life and outcome.

In silico identification of oncogenic potential of fyn-related kinase in hepatocellular carcinoma

MOTIVATION

Cancer development is a complex and heterogeneous process. It is estimated that 5-10% of human genes probably contribute to oncogenesis, whereas current experimentally validated cancer genes only cover 1% of the human genome. Thus hundreds of cancer genes may still remain to be identified. To search for new genes that play roles in carcinogenesis and facilitate cancer research, we developed a systematic workflow to use information saved in a previously established tumor-associated gene (TAG) database.

RESULTS

By exploiting the information of conserved protein domains from the TAG, we identified 183 potential new TAGs. As a proof-of-concept, one predicted oncogene, fyn-related kinase (FRK), which shows an aberrant digital expression pattern in liver cancer cells, was selected for further investigation. Using 68 paired hepatocellular carcinoma samples, we found that FRK was up-regulated in 52% of cases (P < 0.001). Tumorigenic assays performed in Hep3B and HepG2 cell lines revealed a significant correlation between the level of FRK expression and invasiveness, suggesting that FRK is a positive regulator of invasiveness in liver cancer cells.

CONCLUSION

These findings implied that FRK is a multitalented signal transduction molecule that produces diverse biological responses in different cell types in various microenvironments. In addition, our data demonstrated the accuracy of computational prediction and suggested that other predicted TAGs can be potential targets for future cancer research.

AVAILABILITY

The TAG database is available online at the Bioinformatics Center website: http://www.binfo.ncku.edu.tw/TAG/.

Inhibition of constitutively activated phosphoinositide 3-kinase/AKT pathway enhances antitumor activity of chemotherapeutic agents in breast cancer susceptibility gene 1-defective breast cancer cells

Loss or decrease of wild type BRCA1 function, by either mutation or reduced expression, has a role in hereditary and sporadic human breast and ovarian cancers. We report here that the PI3K/AKT pathway is constitutively active in BRCA1-defective human breast cancer cells. Levels of phospho-AKT are sustained even after serum starvation in breast cancer cells carrying deleterious BRCA1 mutations. Knockdown of BRCA1 in MCF7 cells increases the amount of phospho-AKT and sensitizes cells to small molecule protein kinase inhibitors (PKIs) targeting the PI3K/AKT pathway. Restoration of wild type BRCA1 inhibits the activated PI3K/AKT pathway and de-sensitizes cells to PKIs targeting this pathway in BRCA1 mutant breast cancer cells, regardless of PTEN mutations. In addition, clinical PI3K/mTOR inhibitors, PI-103, and BEZ235, showed anti-proliferative effects on BRCA1 mutant breast cancer cell lines and synergism in combination with chemotherapeutic drugs, cisplatin, doxorubicin, topotecan, and gemcitabine. BEZ235 synergizes with the anti-proliferative effects of gemcitabine by enhancing caspase-3/7 activity. Our results suggest that the PI3K/AKT pathway can be an important signaling pathway for the survival of BRCA1-defective breast cancer cells and pharmacological inhibition of this pathway is a plausible treatment for a subset of breast cancers.

Sapacitabine for cancer

INTRODUCTION

Sapacitabine is an orally bioavailable nucleoside analog prodrug that is in clinical trials for hematologic malignancies and solid tumors. The active metabolite of sapacitabine, CNDAC (2'-C-cyano-2'-deoxy-1-β-D-arabino-pentofuranosylcytosine), exhibits the unique mechanism of action of causing single-strand breaks (SSBs) after incorporation into DNA, which are converted into double-strand breaks (DSBs) when cells enter a second S-phase. CNDAC-induced DSBs are predominantly repaired through homologous recombination (HR). Cells deficient in HR components are greatly sensitized to CNDAC. Therefore, sapacitabine could be specifically effective against tumors that are deficient in this repair pathway.

AREAS COVERED

This review summarizes results from supporting evidence for the mechanisms of action of sapacitabine, its preclinical activities and the current results of clinical trials in a variety of cancers. The novel action mechanism of sapacitabine is discussed, with a view to validate it as a chemotherapeutic drug targeting malignancies with defects in HR.

EXPERT OPINION

Knowledge of CNDAC mechanism identifies tumors that may be sensitized to sapacitabine, thus enabling a personalized treatment strategy. It also creates the opportunity to overcome resistance to current front-line therapies and identify synergistic interactions with known anticancer drugs. The results of such investigations may provide rationales for the design of sapacitabine-based clinical trials.

BRCA mutation status and determinant of outcome in women with recurrent epithelial ovarian cancer treated with pegylated liposomal doxorubicin

Epithelial ovarian cancer (EOC) patients with BRCA mutations (BRCA +) benefit from platinum-based treatment more than noncarriers. Impaired ability to repair DNA by homologous recombination increases their chemosensitivity. We investigated whether BRCA + predicts for improved outcome following pegylated liposomal doxorubicin (PLD) for recurrence. Recurrent EOC patients receiving second- or third-line PLD from 1998 to 2009 in 4 institutions (Tel Aviv, New York, Padua, and Jerusalem) were subjected to retrospective comparisons between 40 (25.8%) patients who were BRCA +, and 115 (74.2%) deemed nonhereditary (NH). Median age was 59 years (range 31-83); 111 (72%) had a platinum-free interval more than 6 months [PLD alone (n = 65) and PLD plus platinum (n = 90)]; 104 received PLD in second-line and 51 in third-line. BRCA + versus NH comparisons: median time to treatment failure (TTF) 15.8 months [95% confidence interval (CI): 11.4-21.6] versus 8.1 months (95% CI: 6.1-10.3; P = 0.009); overall survival (OS) 56.8 months (95% CI: 32.5-indeterminate) versus 22.6 months (95% CI: 17.0-34.1; P = 0.002). In multivariate Cox models BRCA status was significantly associated with TTF (HR = 1.66; 95% CI: 1.08-2.55; P = 0.02) and OS (adjusted HR 2.07; 95% CI: 1.18-3.60; P = 0.01). Adjusted HR relating platinum sensitivity to OS was 1.58 (95% CI: 0.93-2.68; P = 0.09); no significant association found with age at diagnosis, line of PLD or combinations, or institution. In this retrospective analysis, recurrent EOC BRCA mutation carriers treated with PLD had an improved outcome, and this result seemed to be independent of platinum sensitivity. Tumors arising in a background of defective BRCA function are more sensitive than other EOCs to DNA-damaging agents such as PLD, even after acquiring platinum resistance.

Drug therapy for hereditary cancers

Tumors arising in patients with hereditary cancer syndromes may have distinct drug sensitivity as compared to their sporadic counterparts. Breast and ovarian neoplasms from BRCA1 or BRCA2 mutation carriers are characterized by deficient homologous recombination (HR) of DNA, that makes them particularly sensitive to platinum compounds or inhibitors of poly (ADP-ribose) polymerase (PARP). Outstandingly durable complete responses to high dose chemotherapy have been observed in several cases of BRCA-related metastatic breast cancer (BC). Multiple lines of evidence indicate that women with BRCA1-related BC may derive less benefit from taxane-based treatment than other categories of BC patients. There is virtually no reports directly assessing drug response in hereditary colorectal cancer (CRC) patients; studies involving non-selected (i.e., both sporadic and hereditary) CRC with high-level microsatellite instability (MSI-H) suggest therapeutic advantage of irinotecan. Celecoxib has been approved for the treatment of familial adenomatous polyposis (FAP). Hereditary medullary thyroid cancers (MTC) have been shown to be highly responsive to a multitargeted tyrosine kinase inhibitor vandetanib, which exerts specific activity towards mutated RET receptor. Given the rapidly improving accessibility of DNA analysis, it is foreseen that the potential predictive value of cancer-associated germ-line mutations will be increasingly considered in the future studies.

Other options in the treatment of advanced breast cancer

Many cytotoxic therapies are available for patients with metastatic breast cancer, but response rates are low and acquired or de novo resistance is virtually universal. Among the agents that are used in the treatment of pretreated metastatic breast cancer are vinorelbine, gemcitabine, nab-paclitaxel, pemetrexed, platinum salts (eg, cisplatin, carboplatin), pegylated liposomal doxorubicin, etoposide, and irinotecan. Therapies that improve overall survival in patients with anthracycline- and taxane-resistant metastatic breast cancer are needed.

Immunophenotypic predictive profiling of BRCA1-associated breast cancer

The immunophenotypic predictive profile of BRCA1-associated cancers including major predictive markers, i.e., PARP-1, EGFR, c-kit, HER-2, and steroid hormones (ER/PR) that may have therapeutic relevance has not yet been reported in a comprehensive study. Using immunohistochemistry, we examined the expression of these proteins in a large cohort of BRCA1-associated breast cancers. PARP-1 immunoreactivity was found in 81.9%, EGFR in 43.6%, ER/PR in 17.9%, c-kit in 14.7%, and overexpression of HER-2 in 3.6% of cancers. For all markers studied, 8.2% of tumors were negative. Expression of only one predictive marker was found in 29.7% of cancers, and most frequently, it was PARP-1 (20.8%). In 62.1% of tumors, more than one predictive marker was expressed: PARP-1 and EGFR in 30.4%, PARP-1, and hormone receptors in 13.3% and PARP-1 with c-kit in 7.5% of all tumors. Coexpression of two or more other predictive markers was rare. There were significant differences in the median age at diagnosis of BRCA1-associated cancer between patients with ER+ vs. ER- and grades 1-2 vs. grade 3 tumors. These results demonstrate that BRCA1-associated cancers differ with respect to expression of proteins that are regarded as targets for specific therapies and that 92% of patients with BRCA1-associated cancers may benefit from one or several options for specific therapy (in addition to DNA damaging agents, e.g., cisplatin). About 8% of cancers which do not express therapeutic target proteins may not respond to such therapies. Knowledge of the immunophenotypic predictive profile may help with the recruitment of patients for trials of targeted therapies.

Increased Incidence of Visceral Metastases in Scottish Patients With BRCA1/2-Defective Ovarian Cancer: An Extension of the Ovarian BRCAness Phenotype

Purpose

To compare the frequency of visceral relapse of BRCA1/2-deficient ovarian cancer to that of nonhereditary controls.

Patients and Methods

All patients diagnosed in Scotland with epithelial ovarian cancer (EOC) or primary peritoneal cancer (PPC) and a germline BRCA1/2 mutation were identified. Those with previous malignancy were excluded. Each remaining patient who experienced relapse was matched with two nonhereditary controls.

Results

Seventy-nine patients with EOC/PPC and germline BRCA1/2 mutations were identified. Fifteen had inadequate clinical data, two had carcinosarcoma, 27 had previous breast cancer, and 16 were in remission. Of the remaining 19 patients who were BRCA1/2 deficient, 14 patients (74%) developed visceral metastases compared with six (16%) of 38 patients in the control group. The percentages of liver, lung, and splenic metastases were 53%, 32%, and 32%, respectively, in the patients compared with 5%, 3%, and 5%, respectively, in the controls. When events occurring outside the matched follow-up period were omitted, the percentages of visceral, liver, lung, and splenic metastases were 58%, 42%, 16%, and 32% in the patients compared with 5%, 0%, 0%, and 3% in controls (P < .001, P < .001, P = .066, and P = .011, respectively). In an independent validation set, the corresponding percentages of visceral, liver, lung, and splenic metastases were 63%, 46%, 13%, and 17% in the patients compared with 11%, 4%, 2%, and 2% in controls (P < .001, P < .001, P = .153, and P = .052, respectively).

Conclusion

Although sporadic EOC commonly remains confined to the peritoneum, BRCA1/2-deficient ovarian cancer frequently metastasizes to viscera. These data extend the ovarian BRCAness phenotype, imply BRCA1/2-deficient ovarian cancer is biologically distinct, and suggest that patients with visceral metastases should be considered for BRCA1/2 sequencing.

Biomarkers in bronchopulmonary cancer

Non-small-cell lung cancer (NSCLC) ranks among the neoplasms with the worst prognoses and the highest mortality rates. Several factors, mainly clinical, are known that provide a predictive value on the course of the disease. In the era in which we live, the molecular basis of cancer is studied in depth and several molecular markers have been described that could play a prognostic role or that could predict the probability of responding to the different treatments used. Moreover, some mechanisms have been proposed that could explain primary or acquired resistance to treatment with chemotherapy and to targeted therapies. Knowing all these pathways is very important, as it allows the development of selective therapeutic strategies that minimise toxicity and optimise treatment effectiveness. However, the data obtained yield results that are at times contradictory, prospective studies with biomarkers thus being necessary so that their role can be established with the necessary evidence.

ERalpha-negative and triple negative breast cancer: molecular features and potential therapeutic approaches

Triple negative breast cancer (TNBC) is a type of aggressive breast cancer lacking the expression of estrogen receptors (ER), progesterone receptors (PR) and human epidermal growth factor receptor-2 (HER-2). TNBC patients account for approximately 15% of total breast cancer patients and are more prevalent among young African, African-American and Latino women patients. The currently available ER-targeted and Her-2-based therapies are not effective for treating TNBC. Recent studies have revealed a number of novel features of TNBC. In the present work, we comprehensively addressed these features and discussed potential therapeutic approaches based on these features for TNBC, with particular focus on: 1) the pathological features of TNBC/basal-like breast cancer; 2) E(2)/ERbeta-mediated signaling pathways; 3) G-protein coupling receptor-30/epithelial growth factor receptor (GPCR-30/EGFR) signaling pathway; 4) interactions of ERbeta with breast cancer 1/2 (BRCA1/2); 5) chemokine CXCL8 and related chemokines; 6) altered microRNA signatures and suppression of ERalpha expression/ERalpha-signaling by micro-RNAs; 7) altered expression of several pro-oncongenic and tumor suppressor proteins; and 8) genotoxic effects caused by oxidative estrogen metabolites. Gaining better insights into these molecular pathways in TNBC may lead to identification of novel biomarkers and targets for development of diagnostic and therapeutic approaches for prevention and treatment of TNBC.

Co-existence of breast and ovarian cancers in BRCA germ-line mutation carriers

The co-existence of breast and ovarian cancers in the same individual should raise suspicion of a hereditary process. Patients with either BRCA1 or BRCA2 germ-line mutations have an average risk of 39% and 11% respectively of developing ovarian cancer by the age of 70; they have a risk of 35-85% of developing breast cancer in their lifetime. We report here unusual pathologic features in a BRCA2 germ-line mutation carrier recently diagnosed with synchronous breast and ovarian cancers, and summarize the findings in six other women who were diagnosed with ovarian cancer either simultaneously with the diagnosis of breast cancer or at varying times after the diagnosis. While in most instances this may be a coincidental occurrence in highly susceptible individuals, the patient we highlight raises the provocative hypothesis that at times breast cancer metastasizes to the ovaries of mutation carriers and stimulates the development of an ovarian cancer as well as other cancers. In addition, these ovarian cancers may have different mechanisms of metastases predisposing them to travel to unusual sites.