Chemoprevention of familial adenomatous polyposis

Antitumor efficacy of intermittent low-dose erlotinib plus sulindac via MHC upregulation and remodeling of the immune cell niche

A previously reported clinical trial in familial adenomatous polyposis (FAP) patients treated with erlotinib plus sulindac (ERL + SUL) highlighted immune response/interferon-γ signaling as a key pathway. In this study, we combine intermittent low-dose ERL ± SUL treatment in the polyposis in rat colon (Pirc) model with mechanistic studies on tumor-associated immune modulation. At clinically relevant doses, short-term (16 weeks) and long-term (46 weeks) ERL ± SUL administration results in near-complete tumor suppression in Pirc colon and duodenum (p < 0.0001). We identify a low-dose threshold for significant antitumor activity in Pirc rats given SUL at 125 ppm in the diet plus ERL at 5 mg/kg body weight via twice-weekly oral gavage (SUL125 + ERL5 × 2). Longitudinal analyses show diminished expression of MHC class I and II genes in polyps larger than Grade 5, a novel finding in the Pirc model. Treatment with ERL ± SUL upregulates the corresponding MHC and immune-associated factors in a subset of Pirc colon polyps, Pirc tumor cell lines, murine colon carcinoma cells, and FAP patient-derived organoids, with Nlrc5 playing a critical role in this effect. Imaging mass cytometry reveals that SUL125 + ERL5 × 2 increases tumor-associated Cd4+ T cells by ~2.6-fold (p < 0.05), with no apparent effect on Cd8+ T cells. The treatment also increases tumor-associated Cd68+ cells (p < 0.05) and decreases Foxp3+ (p < 0.01) and Arg1+ (p < 0.05) cells. Thus, intermittent low-dose ERL + SUL treatment enhances tumor-associated MHC expression and remodels the immune cell niche toward a more permissive "helper" immune microenvironment. We conclude that early immune-interception strategies targeting interferon-γ signaling may benefit FAP patients at drug doses below the clinical standard of care.

Downregulation of ABCC3 activates MAPK signaling through accumulation of deoxycholic acid in colorectal cancer cells

ABCC3 (also known as MRP3) is an ATP binding cassette transporter for bile acids, whose expression is downregulated in colorectal cancer through the Wnt/β-catenin signaling pathway. However, it remained unclear how downregulation of ABCC3 expression contributes to colorectal carcinogenesis. We explored the role of ABCC3 in the progression of colorectal cancer-in particular, focusing on the regulation of bile acid export. Gene expression analysis of colorectal adenoma isolated from familial adenomatous polyposis patients revealed that genes related to bile acid secretion including ABCC3 were downregulated as early as at the stage of adenoma formation. Knockdown or overexpression of ABCC3 increased or decreased intracellular concentration of deoxycholic acid, a secondary bile acid, respectively, in colorectal cancer cells. Forced expression of ABCC3 suppressed deoxycholic acid-induced activation of MAPK signaling. Finally, we found that nonsteroidal anti-inflammatory drugs increased ABCC3 expression in colorectal cancer cells, suggesting that ABCC3 could be one of the targets for therapeutic intervention of familial adenomatous polyposis. Our data thus suggest that downregulation of ABCC3 expression contributes to colorectal carcinogenesis through the regulation of intracellular accumulation of bile acids and activity of MAPK signaling.

Chemoprevention in Inherited Colorectal Cancer Syndromes

Cancer prevention in hereditary gastrointestinal predisposition syndromes relies primarily on intensive screening (e.g., colonoscopy) or prophylactic surgery (e.g., colectomy). The use of chemopreventive agents as an adjunct to these measures has long been studied both in the general population and in hereditary cancer patients, in whom the risk of malignancy, and therefore the potential risk reduction, is considerably greater. However, to date only few compounds have been found to be effective, safe, and tolerable for widespread use. Furthermore, many of the studies involving these rare syndromes suffer from small sample sizes, heterogeneous patient cohorts, short follow-up duration, and lack of standardized endpoints, creating challenges to draw generalizable conclusion regarding efficacy. The following review summarizes the current data on various chemopreventive compounds used in Lynch syndrome and familial adenomatous polyposis in addition to several agents that are currently being investigated.

Management of Desmoid Disease in Familial Adenomatous Polyposis

Desmoid disease, though technically a benign condition, is nevertheless a leading cause of morbidity and mortality in patients with familial adenomatous polyposis (FAP). Desmoid disease impacts approximately 30% of FAP patients, with several known risk factors. It runs the gamut in terms of severity-ranging from small, slow-growing asymptomatic lesions to large, focally destructive, life-threatening masses. Desmoids usually occur following surgery, and several patient risk factors have been established, including female sex, family history of desmoid disease, 3' APC mutation, and extraintestinal manifestations of FAP. Desmoid disease-directed therapy is individualized and impacted by desmoid stage, severity, postsurgical anatomy, and consequences of disease. Medical therapy consists of options in multiple classes of drugs: nonsteroidal anti-inflammatory drugs, hormonal therapy, tyrosine kinase inhibitors, and cytotoxic agents. Surgical excision is sometimes an option, but can be limited by common location of disease at the root of the small bowel mesentery. Palliative surgical treatments are often considered in management of desmoid disease. Intestinal transplantation for severe desmoid disease is an emerging and promising option, though long-term data on efficacy and survival is limited.

Endoscopic and chemopreventive management of familial adenomatous polyposis syndrome

Familial adenomatous polyposis (FAP) is an autosomal dominant syndrome predisposing affected individuals to gastrointestinal (GI) cancers through a high burden of polyposis. Colorectal cancer rates reach 100% by the age of 45, making early colectomy a mainstay of treatment. While most patients undergo colectomy at an early age, ongoing screening and surveillance of the upper gastrointestinal tract and rectal pouch must continue throughout adulthood. Endoscopic therapy of gastric, duodenal, ampullary and rectal pouch polyps is critical to reduce morbidity and cancer related mortality. Management of these lesions is not uniform, and is dependent on their location, size, histology, and risk of malignant potential. Medical therapies targeting pathways that reduce the malignant progression of pre-cancerous lesions have been studied for many years. While studies on the use of aspirin and non-steroidal anti-inflammatories (NSAIDs) in chemoprevention have shown encouraging results in Lynch syndrome and primary colorectal cancer, the potential benefits of these medications have not been duplicated in FAP cohorts. While data remains limited on chemoprevention in FAP, a number of randomized trials are currently underway examining targeted therapies with the potential to slow the progression of the disease. This review aims to provide an in-depth review of the literature on current endoscopic options and chemopreventive therapies targeting FAP. While the endoscopic management has robust data for its use, chemoprevention in FAP is still in its infancy. The complementary use of chemopreventive agents and endoscopic therapy for FAP patients is quickly becoming a growing and exciting area of research.

A Review of the Clinical Presentation, Outcomes, and Treatments of Patients Having Desmoid Tumors

Desmoid tumors (DTs) are deep fibroblastic neoplasms that arise from musculo-aponeurotic stromal elements. DTs may result in significant morbidity by infiltrating vital anatomic structures. Their mortality is often due to the local aggressiveness, most commonly when intra-abdominal in location. Some indolent DTs can be observed expectantly; infiltrative tumors require an aggressive and multidisciplinary approach and are offered conservative therapies such as nonsteroidal anti-inflammatory drugs or antiestrogens when surgery is not feasible. Comparably, chemotherapy is considered for those cases not amenable to surgery or radiation. Bowel resection and at times intestinal transplantation may be necessary. However, DTs may recur postsurgery making long-term management of these patients. Herein, we review the genetics, clinical presentations, outcomes, and treatments of DTs.

Combination Chemotherapy of Multidrug-resistant Early-stage Colon Cancer: Determining Optimal Dose Schedules by High-performance Computer Simulation

The goal of this project was to utilize mechanistic simulation to demonstrate a methodology that could determine drug combination dose schedules and dose intensities that would be most effective in eliminating multidrug resistant cancer cells in early-stage colon cancer. An agent-based model of cell dynamics in human colon crypts was calibrated using measurements of human biopsy specimens. Mutant cancer cells were simulated as cells that were resistant to each of two drugs when the drugs were used separately. The drugs, 5-flurouracil and sulindac, have different mechanisms of action. An artificial neural network was used to generate nearly two hundred thousand two-drug dose schedules. A high-performance computer simulated each dose schedule as a in silico clinical trial and evaluated each dose schedule for its efficiency to cure (eliminate) multidrug resistant cancer cells and its toxicity to the host, as indicated by continued crypt function. Among the dose schedules that were generated, 2430 dose schedules were found to cure all multidrug resistant mutants in each of the 50 simulated trials and retained colon crypt function. One dose schedule was optimal; it eliminated multidrug resistant cancer cells with the minimum toxicity and had a time schedule that would be practical for implementation in the clinic. These results demonstrate a procedure to identify which combination drug dose schedules could be most effective in eliminating drug resistant cancer cells. This was accomplished using a calibrated agent-based model of a human tissue, and a high-performance computer simulation of clinical trials.

Recent advances in the development of celecoxib analogs as anticancer agents: A review

Celecoxib is a nonsteroidal anti-inflammatory drug (NSAID) designed to be a selective cyclooxygenase-2 (COX-2) inhibitor. It was approved by the U.S. Food and Drug Administration for the treatment of inflammatory diseases such as osteoarthritis and rheumatoid arthritis. Additionally, celecoxib demonstrated potent antitumor and chemopreventive effects in vitro, in vivo, and in patients. The mechanism of celecoxib's chemopreventive effect is still not fully identified, but it is assumed to be multifactorial. Celecoxib's anticancer activity has been described both as independent of and dependent on its COX-2 inhibitory activity. The current review summarizes the recent advances published between 2000 and 2022 on the structure-based optimization of celecoxib to develop compounds with promising anticancer activity. The structure-activity relationships of celecoxib analogs are discussed, which may be beneficial in the design and development of novel analogs as potent antiproliferative agents in the future.

Drug Repurposing Strategies for Non-Cancer to Cancer Therapeutics

Global efforts invested for the prevention and treatment of cancer need to be repositioned to develop safe, effective, and economic anticancer therapeutics by adopting rational approaches of drug discovery. Drug repurposing is one of the established approaches to reposition old, clinically approved off patent noncancer drugs with known targets into newer indications. The literature review suggests key role of drug repurposing in the development of drugs intended for cancer as well as noncancer therapeutics. A wide category of noncancer drugs namely, drugs acting on CNS, anthelmintics, cardiovascular drugs, antimalarial drugs, anti-inflammatory drugs have come out with interesting outcomes during preclinical and clinical phases. In the present article a comprehensive overview of the current scenario of drug repurposing for the treatment of cancer has been focused. The details of some successful studies along with examples have been included followed by associated challenges.

Combining repurposed drugs to treat colorectal cancer

The drug development process, especially of antineoplastic agents, has become increasingly costly and ineffective. Drug repurposing and drug combination are alternatives to de novo drug development, being low cost, rapid, and easy to apply. These strategies allow higher efficacy, decreased toxicity, and overcoming of drug resistance. The combination of antineoplastic agents is already being applied in cancer therapy, but the combination of repurposed drugs is still under-explored in pre- and clinical development. In this review, we provide a set of pharmacological concepts focusing on drug repurposing for treating colorectal cancer (CRC) and that are relevant for the application of new drug combinations against this disease.

Celecoxib Analogues for Cancer Treatment: An Update on OSU-03012 and 2,5-Dimethyl-Celecoxib

Cyclooxygenase-2 (COX-2) is an important enzyme involved in prostaglandins biosynthesis from arachidonic acid. COX-2 is frequently overexpressed in human cancers and plays a major tumor promoting function. Accordingly, many efforts have been devoted to efficiently target the catalytic site of this enzyme in cancer cells, by using COX-2 specific inhibitors such as celecoxib. However, despite their potent anti-tumor properties, the myriad of detrimental effects associated to the chronic inhibition of COX-2 in healthy tissues, has considerably limited their use in clinic. In addition, increasing evidence indicate that these anti-cancerous properties are not strictly dependent on the inhibition of the catalytic site. These findings have led to the development of non-active COX-2 inhibitors analogues aiming at preserving the antitumor effects of COX-2 inhibitors without their side effects. Among them, two celecoxib derivatives, 2,5-Dimethyl-Celecoxib and OSU-03012, have been developed and suggested for the treatment of viral (e.g., recently SARS-CoV-2), inflammatory, metabolic diseases and cancers. These molecules display stronger anti-tumor properties than celecoxib and thus may represent promising anti-cancer molecules. In this review, we discuss the impact of these two analogues on cancerous processes but also their potential for cancer treatment alone or in combination with existing approaches.

Definition and management of colorectal polyposis not associated with APC/MUTYH germline pathogenic variants: AIFEG consensus statement

An expert consensus panel convened by the Italian Association for Inherited and Familial Gastrointestinal Tumors (Associazione Italiana per lo Studio della Familiarità ed Ereditarietà dei Tumori Gastrointestinali, AIFEG) reviewed the literature and agreed on a number of position statements regarding the definition and management of polyposis coli without an identified pathogenic mutation on the APC or MUTYH genes, defined in the document as NAMP (non-APC/MUTYH polyposis).

Optimization of Erlotinib Plus Sulindac Dosing Regimens for Intestinal Cancer Prevention in an Apc-Mutant Model of Familial Adenomatous Polyposis (FAP)

A clinical trial in patients with familial adenomatous polyposis (FAP) demonstrated that sulindac plus erlotinib (SUL+ERL) had good efficacy in the duodenum and colon, but toxicity issues raised concerns for long-term prevention. We performed a biomarker study in the polyposis in rat colon (Pirc) model, observing phosphorylated Erk inhibition in colon polyps for up to 10 days after discontinuing ERL+SUL administration. In a follow-up study lasting 16 weeks, significant reduction of colon and small intestine (SI) tumor burden was detected, especially in rats given 250 ppm SUL in the diet plus once-a-week intragastric dosing of ERL at 21 or 42 mg/kg body weight (BW). A long-term study further demonstrated antitumor efficacy in the colon and SI at 52 weeks, when 250 ppm SUL was combined with once-a-week intragastric administration of ERL at 10, 21, or 42 mg/kg BW. Tumor-associated matrix metalloproteinase-7 (Mmp7), tumor necrosis factor (Tnf), and early growth response 1 (Egr1) were decreased at 16 weeks by ERL+SUL, and this was sustained in the long-term study for Mmp7 and Tnf. Based on the collective results, the optimal dose combination of ERL 10 mg/kg BW plus 250 ppm SUL lacked toxicity, inhibited molecular biomarkers, and exhibited effective antitumor activity. We conclude that switching from continuous to once-per-week ERL, given at one-quarter of the current therapeutic dose, will exert good efficacy with standard-of-care SUL against adenomatous polyps in the colon and SI, with clinical relevance for patients with FAP before or after colectomy. PREVENTION RELEVANCE: This investigation concludes that switching from continuous to once-per-week erlotinib, given at one-quarter of the current therapeutic dose, will exert good efficacy with standard-of-care sulindac against adenomatous polyps in the colon and small intestine, with clinical relevance for patients with FAP before or after colectomy.

Sulindac plus a phospholipid is effective for polyp reduction and safer than sulindac alone in a mouse model of colorectal cancer development

Background

Non-steroidal anti-inflammatory drugs (NSAIDs) such as aspirin and sulindac are effective for colorectal cancer prevention in humans and some animal models, but concerns over gastro-intestinal (GI) ulceration and bleeding limit their potential for chemopreventive use in broader populations. Recently, the combination of aspirin with a phospholipid, packaged as PL-ASA, was shown to reduce GI toxicity in a small clinical trial. However, these studies were done for relatively short periods of time. Since prolonged, regular use is needed for chemopreventive benefit, it is important to know whether GI safety is maintained over longer use periods and whether cancer prevention efficacy is preserved when an NSAID is combined with a phospholipid.

Methods

As a first step to answering these questions, we treated seven to eight-week-old, male and female C57B/6 Apc^min/+ mice with the NSAID sulindac, with and without phosphatidylcholine (PC) for 3-weeks. At the end of the treatment period, we evaluated polyp burden, gastric toxicity, urinary prostaglandins (as a marker of sulindac target engagement), and blood chemistries.

Results

Both sulindac and sulindac-PC treatments resulted in significantly reduced polyp burden, and decreased urinary prostaglandins, but sulindac-PC treatment also resulted in the reduction of gastric lesions compared to sulindac alone.

Conclusions

Together these data provide pre-clinical support for combining NSAIDs with a phospholipid, such as phosphatidylcholine to reduce GI toxicity while maintaining chemopreventive efficacy.

Recent Advances in Desmoid Tumor Therapy

The desmoid tumor is a locally aggressive proliferative disease within the family of soft-tissue sarcomas. Despite its relatively good prognosis, the clinical management of desmoid tumors requires constant multidisciplinary evaluation due to its highly variable clinical behavior. Recently, active surveillance has being regarded as the appropriate strategy at diagnosis, as indolent persistence or spontaneous regressions are not uncommon. Here, we review the most recent advances in desmoid tumor therapy, including low-dose chemotherapy and treatment with tyrosine kinase inhibitors. We also explore the recent improvements in our knowledge of the molecular biology of this disease, which are leading to clinical trials with targeted agents.

Prevention of Colon Cancer Recurrence From Minimal Residual Disease: Computer Optimized Dose Schedules of Intermittent Apoptotic Adjuvant Therapy

PURPOSE

Adjuvant chemotherapy is used after surgery for stages II and III colorectal cancer to reduce recurrence. Nevertheless, recurrence may occur years later with the emergence of initially undetected minimal residual disease (MRD). Attempts to reduce recurrence by increasing the dose intensity and increasing the time of adjuvant therapy have been limited by the adverse effects of the recommended cytotoxic agents. The goals of this study were to suggest an alternative to the recommended cytotoxic agents and to determine optimal adjuvant therapy dose schedules that would reduce the percentage of recurrence at 5 years while retaining colon crypt function.

METHODS

A total of 84,400 dose schedules with different duration, interval between doses, and intensity of treatment were simulated with a high-performance computer. Simulated treatments used the drug sulindac, which had previously been used in primary prevention. With appropriate dose schedules, it can induce apoptosis at the crypt lumen surface while retaining crypt function. We used a computer model of cell dynamics in colon crypts that had been calibrated with measurements of human biopsy specimens. Proliferating mutant cells were assumed to emerge from MRD within crypts. Simulated outcomes included the recurrence percentage at 5 years and the retention of crypt function.

RESULTS

Optimal dose schedules were determined for adjuvant treatment of MRD that reduced the percentage of recurrence at 5 years of stages I, II, and III colon cancer to zero.

CONCLUSION

A new adjuvant therapy for colon cancer based upon optimum dose schedules of intermittent apoptotic treatment may prevent the recurrence of colon cancer from MRD and avoid the adverse effects of cytotoxic treatments.

ETHE1 overexpression promotes SIRT1 and PGC1α mediated aerobic glycolysis, oxidative phosphorylation, mitochondrial biogenesis and colorectal cancer

Ethylmalonic Encephalopathy Protein 1 (ETHE1) is a sulfur dioxygenase that regulates cellular H2S levels. We previously demonstrated a significant increase of ETHE1 expression in "single-hit" colon epithelial cells from crypts of patients with Familial Adenomatous Polyposis (FAP). Here, we report elevated levels of ETHE1 expression and increased mitochondrial density occurring in-situ in phenotypically normal FAP colorectal mucosa. We also found that constitutive expression of ETHE1 increased aerobic glycolysis ("Warburg effect"), oxidative phosphorylation, and mitochondrial biogenesis in colorectal cancer (CRC) cell lines, thereby depleting H2S which relieved the inhibition of phosphodiesterase (PDE), and increased adenosine monophosphate (AMP) levels. This led to activation of the energy sensing AMP-activated protein kinase (AMPKp), Sirtuin1 (SIRT1) and peroxisome proliferator-activated receptor γ coactivator 1α (PGC1α), a master regulator of mitochondrial biogenesis. By contrast, shRNA silencing of ETHE1 reduced PDE activity, AMPKp/SIRT1/PGC1α levels and mitochondrial biogenesis. Constitutive expression of ETHE1 accelerated both CRC cell xenograft and orthotopic patient derived xenograft CRC cell growth in vivo. Overall, our data nominate elevated ETHE1 expression levels as a novel biomarker and potential therapeutic target for the prevention of CRC tumorigenesis.

Drug repurposing in oncology: Compounds, pathways, phenotypes and computational approaches for colorectal cancer

The strategy of using existing drugs originally developed for one disease to treat other indications has found success across medical fields. Such drug repurposing promises faster access of drugs to patients while reducing costs in the long and difficult process of drug development. However, the number of existing drugs and diseases, together with the heterogeneity of patients and diseases, notably including cancers, can make repurposing time consuming and inefficient. The key question we address is how to efficiently repurpose an existing drug to treat a given indication. As drug efficacy remains the main bottleneck for overall success, we discuss the need for machine-learning computational methods in combination with specific phenotypic studies along with mechanistic studies, chemical genetics and omics assays to successfully predict disease-drug pairs. Such a pipeline could be particularly important to cancer patients who face heterogeneous, recurrent and metastatic disease and need fast and personalized treatments. Here we focus on drug repurposing for colorectal cancer and describe selected therapeutics already repositioned for its prevention and/or treatment as well as potential candidates. We consider this review as a selective compilation of approaches and methodologies, and argue how, taken together, they could bring drug repurposing to the next level.

Management of Familial Adenomatous Polyposis in Children and Adolescents: Position Paper From the ESPGHAN Polyposis Working Group

Familial adenomatous polyposis (FAP) is a well-described inherited syndrome, characterized by the development of hundreds to thousands of adenomas in the colorectum, with implications in children and adolescents. Almost all adult patients will develop colorectal cancer if they are not identified and treated early enough. Identifying and screening for FAP commences in adolescence. The syndrome is inherited as an autosomal dominant trait and caused by mutations in the adenomatous polyposis (APC) gene. This European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) position paper provides a guide for diagnosis, assessment, and management of FAP in children and adolescents.This is the first position paper regarding FAP published by ESPGHAN. Literature from PubMed, Medline, and Embase was reviewed and in the absence of evidence, recommendations reflect the opinion of paediatric and adult experts involved in the care of polyposis syndromes. Because many of the studies that form the basis for the recommendations were descriptive and/or retrospective in nature, these of the recommendations are supported on expert opinion. This position paper will instruct on the appropriate management and timing of procedures in children and adolescents with FAP.

Web-Based Model for Predicting Time to Surgery in Young Patients with Familial Adenomatous Polyposis: An Internally Validated Study

INTRODUCTION

The timing of prophylactic colorectal surgery in patients with familial adenomatous polyposis (FAP) is based on the immediacy of the colorectal cancer risk. The ability to predict the need for surgery may help patients and their families plan in the context of life events and CRC risk. We created a model to predict the likelihood of surgery within 2 and 5 years of first colonoscopy at our institution.

METHODS

A single institution hereditary colorectal syndrome (Cologene™) database was interrogated for all patients with FAP having a deleterious APC mutation. Patients with first colonoscopy after age 30 and before year 2000 were excluded. Cox regression analysis was done to assess multiple factors associated with surgery, followed by stepwise Cox regression analysis to select an optimal model. Receiver operator curve (ROC) analysis was performed to assess the model.

RESULTS

A total of 211 (53% female) patients were included. Forty-five percent underwent surgery after an average of 3.8 years of surveillance. The final model was created based on initial clinical characteristics (age, gender, BMI, family history of desmoids, genotype-phenotype correlation), initial colonoscopic characteristics (number of polyps, polyp size, presence of high-grade dysplasia); and on clinical events (chemoprevention and polypectomy). AUC was 0.87 and 0.84 to predict surgery within 2 and 5 years, respectively. The final model can be accessed at this website: http://app.calculoid.com/#/calculator/29638 .

CONCLUSION

This web-based tool allows clinicians to stratify patients' likelihood of colorectal surgery within 2 and 5 years of their initial examination, based on clinical and endoscopic features, and using the philosophy of care guiding practice at this institution.

Natural history of colonic polyposis in young patients with familial adenomatous polyposis

BACKGROUND AND AIMS

Proctocolectomy prevents colorectal cancer in familial adenomatous polyposis (FAP). Colorectal polyp progression is one of the indications for surgery. No data exist regarding the natural history of colorectal polyposis in young patients with FAP. This study examined the rate of polyposis progression and factors associated with it.

METHODS

Patients with FAP <30 years old who had undergone ≥2 colonoscopies since 2000 were identified. Rate of polyposis progression was calculated by review of polyp counts obtained from baseline and last colonoscopy, accounting for any polyps removed during the observation period. Endoscopic and non-endoscopic factors affecting the rate of polyposis progression were evaluated. Multivariate analysis was performed to identify factors associated with rate of polyposis progression.

RESULTS

One hundred sixty-eight patients (52% female; median age, 13.5 years) were included. Median rate of polyposis progression was 25.4 polyps/year (interquartile range, 9.5-69.8). Highest median rate of polyposis progression (89 polyps/year) was associated with mutation in codon 1309. The rate of polyposis progression was independently associated with the location of mutation in the adenomatous polyposis coli gene, the number of polyps at the initial colonoscopy, and exposure to chemoprevention. Of the 39.9% of patients who underwent surgery, an increase in polyp number was the most common indication (53.7%).

CONCLUSIONS

The rate of polyposis progression in young patients with FAP varies with a median of about 25 new polyps per year. Progression is associated with distinct factors, which can be used in discussion with patients regarding the need for and timing of prophylactic colorectal surgery.

Alternative treatments for prophylaxis of colorectal cancer in familial adenomatous polyposis

Familial adenomatous polyposis (FAP) is a rare, hereditary disease characterized by the presence of 100 or more adenomas distributed throughout the colon and rectum. If untreated, colorectal cancer develops in almost 100% of FAP patients. As prophylactic treatment, proctocolectomy with ileal pouch-anal anastomosis remains the surgical treatment of choice. High rates of postoperative complications, however, have been reported with this procedure, including bowel dysfunction, incontinence, and reduced female fecundity. Some novel strategies for preventing hereditary colon cancers have been reported. This review summarizes alternative treatments, including the laparoscopic approach, chemoprevention, endoscopic management, and subtotal colectomy combined with endoscopic treatment, for prophylaxis of colorectal cancer in FAP patients.

The effect of pentoxifylline on L-1 sarcoma tumor growth and angiogenesis in Balb/c mice

Methyloxantines are present in many herbs and vegetal foods, among them in tea, coffee and chocolate. Previous studies revealed that theophylline and theobromine have anti-angiogenic properties. Anti-tumor properties of theobromine were also described. Pentoxifylline (3,7-dimethyl-1-(5-oxohexyl)xanthine, PTX) is a synthetic xanthine derivative. It is a phosphodiesterase inhibitor and has various anti-inflammatory abilities. Pentoxifylline is widely used in therapy of inflammatory arterial diseases such as intermittent claudication of upper and lower limbs as well as in coronary heart disease. The aim of our research was to evaluate the effect of pentoxifylline (individually and in combination with non-steroidal anti-inflammatory drug sulindac), on L-1 sarcoma angiogenic activity and tumor formation in syngeneic Balb/c mice. Pre-incubation of tumor cells for 90 min with various PTX concentrations resulted in dose-dependent decrease of their ability to induce newly-formed blood vessels after transplantation into the skin of recipient mice. Administration of PTX to mice, recipients of tumor cells, slows tumor growth and reduces its volume. Synergistic inhibitory effect of PTX and sulindac, expressed as % of tumors sixth and thirteen day after subcutaneous grafting of L-1 sarcoma into syngeneic Balb/c mice, was observed.

Oncogenic targets Mmp7, S100a9, Nppb and Aldh1a3 from transcriptome profiling of FAP and Pirc adenomas are downregulated in response to tumor suppression by Clotam

Intervention strategies in familial adenomatous polyposis (FAP) patients and other high-risk colorectal cancer (CRC) populations have highlighted a critical need for endoscopy combined with safe and effective preventive agents. We performed transcriptome profiling of colorectal adenomas from FAP patients and the polyposis in rat colon (Pirc) preclinical model, and prioritized molecular targets for prevention studies in vivo. At clinically relevant doses in the Pirc model, the drug Clotam (tolfenamic acid, TA) was highly effective at suppressing tumorigenesis both in the colon and in the small intestine, when administered alone or in combination with Sulindac. Cell proliferation in the colonic crypts was reduced significantly by TA, coincident with increased cleaved caspase-3 and decreased Survivin, β-catenin, cyclin D1 and matrix metalloproteinase 7. From the list of differentially expressed genes prioritized by transcriptome profiling, Mmp7, S100a9, Nppb and Aldh1a3 were defined as key oncogene candidates downregulated in colon tumors after TA treatment. Monthly colonoscopies revealed the rapid onset of tumor suppression by TA in the Pirc model, and the temporal changes in Mmp7, S100a9, Nppb and Aldh1a3, highlighting their value as potential early biomarkers for prevention in the clinical setting. We conclude that TA, an "old drug" repurposed from migraine, offers an exciting new therapeutic avenue in FAP and other high-risk CRC patient populations.