Ustekinumab is a promising option for the treatment of postoperative recurrence of Crohn's disease.

BACKGROUND AND AIM: Postoperative recurrence (POR) following ileocolonic resection is a major concern in patients with Crohn's disease (CD). The role of ustekinumab (UST) in this setting is poorly known. METHODS: All consecutive CD patients with a baseline colonoscopy at 6-12 months from ileocolonic resection showing POR (Rutgeerts score ≥ i2) who were treated with UST after the baseline colonoscopy and with an available post-treatment endoscopy, were extracted from the cohort of the Sicilian Network for Inflammatory Bowel Diseases (SN-IBD). The primary outcome was endoscopic success, defined as reduction of at least one point of Rutgeerts score. The secondary outcome was clinical success, assessed at the end of follow-up. Reasons for clinical failure included mild clinical relapse (Harvey-Bradshaw index 5-7), clinically relevant relapse (Harvey-Bradshaw index > 7), and need for new resection. RESULTS: Forty-four patients were included (mean follow-up: 17.8 ± 8.4 months). The baseline postoperative colonoscopy showed severe POR (Rutgeerts score i3 or i4) in 75.0% of patients. The post-treatment colonoscopy was performed after a mean of 14.5 ± 5.5 months following initiation of UST. Endoscopic success was reported in 22 out of 44 (50.0%) patients, of whom 12 (27.3%) achieved a Rutgeerts score i0 or i1. Clinical success at the end of follow-up was reported in 32 out of 44 patients (72.7%); none of the 12 patients with clinical failure had achieved endoscopic success at post-treatment colonoscopy. CONCLUSIONS: Ustekinumab could be a promising option for the treatment of POR of CD.

SPOSAB ABP 501: A Sicilian Prospective Observational Study of Patients with Inflammatory Bowel Disease Treated with Adalimumab Biosimilar ABP 501.

BACKGROUND AND AIM: There are few clinical data on Adalimumab (ADA) biosimilars in inflammatory bowel disease. We aimed to perform a multicenter, observational, prospective study on safety and effectiveness of ADA biosimilar ABP 501 in patients with inflammatory bowel disease. METHODS: All consecutive patients from the cohort of the Sicilian Network for Inflammatory Bowel Disease treated with ADA biosimilar ABP 501 from February 2019 to February 2020 were enrolled. Patients were divided into three groups: group A, naïve to ADA and naïve to anti-tumor necrosis factors; group B, naïve to ADA and previously exposed to anti-tumor necrosis factors; and group C: switched from ADA originator to ABP 501. RESULTS: A total of 559 patients (median age 39 years; Crohn's disease 88.0%, ulcerative colitis 12.0%) were included, with a follow-up time of 403.4 patient-years. Thirty-six serious adverse events occurred in 36 patients (6.4%; incidence rate [IR]: 8.9 per 100 person-years [PY]). The IR of serious adverse events was higher among patients in group A compared with group C (17.4 vs 4.8 per 100 PY; IR ratio = 3.61; P < 0.001) and among patients in group B compared with group C (16.4 vs 4.8 per 100 PY; IR ratio = 3.42; P = 0.041). Among ADA-naïve patients (group A + B), 188 (85.8%) had a clinical response after 12 weeks, including 165 (75.3%) who achieved steroid-free remission. Higher treatment persistence estimates were reported for patients in group C compared with groups A and B (log-rank P < 0.001). CONCLUSIONS: Safety and effectiveness of ABP 501 seem to be overall similar to those reported for ADA originator. Switching from originator to ABP 501 was safe and effective.

Proteomic Screening and Lasso Regression Reveal Differential Signaling in Insulin and Insulin-like Growth Factor I (IGF1) Pathways.

Insulin and insulin-like growth factor I (IGF1) influence cancer risk and progression through poorly understood mechanisms. To better understand the roles of insulin and IGF1 signaling in breast cancer, we combined proteomic screening with computational network inference to uncover differences in IGF1 and insulin induced signaling. Using reverse phase protein array, we measured the levels of 134 proteins in 21 breast cancer cell lines stimulated with IGF1 or insulin for up to 48 h. We then constructed directed protein expression networks using three separate methods: (i) lasso regression, (ii) conventional matrix inversion, and (iii) entropy maximization. These networks, named here as the time translation models, were analyzed and the inferred interactions were ranked by differential magnitude to identify pathway differences. The two top candidates, chosen for experimental validation, were shown to regulate IGF1/insulin induced phosphorylation events. First, acetyl-CoA carboxylase (ACC) knock-down was shown to increase the level of mitogen-activated protein kinase (MAPK) phosphorylation. Second, stable knock-down of E-Cadherin increased the phospho-Akt protein levels. Both of the knock-down perturbations incurred phosphorylation responses stronger in IGF1 stimulated cells compared with insulin. Overall, the time-translation modeling coupled to wet-lab experiments has proven to be powerful in inferring differential interactions downstream of IGF1 and insulin signaling, in vitro.

Safety and effectiveness of tofacitinib in ulcerative colitis: Data from TOFA-UC, a SN-IBD study.

BACKGROUND: Real-world evidence is needed to determine the value of tofacitinib (TOFA) for the treatment of ulcerative colitis (UC). AIM: To assess the safety and effectiveness of TOFA in clinical practice. METHODS: TOFA-UC is a multicenter, observational study performed among the Sicilian Network for Inflammatory Bowel Disease (SN-IBD). All consecutive patients with UC starting TOFA from its introduction in Sicily (July 2021) to July 2022 were included. RESULTS: 111 patients were included (mean follow-up: 31.7 ± 14.9 weeks; biologic-experienced: 92.8%). Nineteen adverse events were reported (17.1%; incidence rate: 28.2 per 100 patient years), including 11 cases of hypercholesterolemia and 3 infections (no cases of herpes zoster reactivation. At week 8, the rates of clinical response, steroid free clinical remission, and CRP normalization were 74.8%, 45.0%, and 56.9%, respectively, and 68.5%, 51.4%, and 65.2%, respectively, at the end of follow-up. Eighteen patients experienced a loss of response after successful induction (21.7%; incidence rate: 33.2 per 100 patient years). Twenty-six patients (23.4%) discontinued TOFA over time, of whom 3 due to AEs, and 23 to non response or loss of response. CONCLUSIONS: TOFA is safe and effective in patients with UC, including those with history of multiple failures to biological therapies.

Role of ustekinumab in treatment of ulcerative colitis: a narrative review.

The therapeutic armamentarium for gastroenterologists in treating ulcerative colitis (UC) has been rapidly growing since the introduction of monoclonal antibodies directed against anti-TNFs. Ustekinumab is a monoclonal antibody binding the shared p40 subunit of IL-12 and IL-23, and the inhibition of these two cytokines, implicated in host response to microbial pathogens, has demonstrated clinical efficacy in different immune-mediated diseases, including moderate-to-severe UC. This narrative review summarizes the newest clinical evidence regarding the efficacy, effectiveness and safety of ustekinumab in moderate-to-severe UC, including specific situations (pregnancy, breastfeeding, elderly/pediatric populations, extraintestinal manifestations, acute severe UC, pouchitis and dual biological therapy). Finally, positioning is discussed in light of the existing evidence.

Ustekinumab (UST) is a biological drug that has been recently licensed as a novel therapy for ulcerative colitis, one of the two main conditions that constitute inflammatory bowel diseases. UST has been previously successfully used in psoriasis and psoriatic arthritis, two conditions in which dysregulation of the immune system causes inflammation in the skin and joints, and Crohn's disease, a type of inflammatory bowel disease. This led to great interest in the use of UST for treating patients with moderate and severe ulcerative colitis. UST is administered with a weight-based intravenous infusion followed by subcutaneous administration every 8 weeks, which can be performed at home and is effective in reducing symptoms of the disease with a particularly favorable safety profile. These features make UST a suitable option for treating especially elderly and frail patients, as well as patients who did not benefit or had side effects with other biological therapies and patients who also suffer from psoriasis or psoriatic arthritis.

Sarcopenia is a negative predictive factor for endoscopic remission in patients with Crohn's disease treated with biologics.

BACKGROUND: Sarcopenia has been associated with poor prognosis in chronic diseases. AIMS: To investigate the role of sarcopenia in predicting clinical and endoscopic outcomes in patients with Crohn's disease (CD). METHODS: Consecutive CD patients who started biologics between 2014 and 2020 and underwent abdominal magnetic resonance or computed tomography within 6 months from the beginning of the biological therapy were enroled. Sarcopenia was defined as Psoas Muscle Index (PMI) lower than 5.4 cm²/m² (men) and 3.56 cm²/m² (women). Univariate and multivariate analyses were used to evaluate whether sarcopenia could predict steroid-free clinical remission (SFCR), endoscopic remission (ER), hospitalisation and surgery after 12 months of therapy. RESULTS: 358 patients were included. Sarcopenia was found in 18.2% of patients, and it was associated with a lower rate of ER (14.8% vs 47.7%; p = 0.002) after 12 months of therapy, while it was not associated with SFCR (65.1% vs 70.1%; p = 0.435), hospitalisation (9.2% vs 7.8%; p = 0.801) and surgery (3.1% vs 6.1%; p = 0.549). Sarcopenia was identified as a predictor of lack of ER (odds ratio [OR]=5.2; p = 0.006), as well as smoking (OR=2.5; p = 0.028) and perianal disease (OR=2.6; p = 0.020). CONCLUSION: Sarcopenia is a negative prognostic factor for ER in CD patients treated with biologics.

The effectiveness of ustekinumab and vedolizumab as third-line biologic therapy in patients with Crohn's disease.

BACKGROUND: The effectiveness of Ustekinumab (UST) and Vedolizumab (VDZ) in patients with Crohn's disease (CD) as third-line biologic therapies is unclear. AIMS: We performed a multicentre, real-world assessment of the effectiveness of UST and VDZ among highly-refractory patients with CD. METHODS: Data of consecutive patients with CD treated with UST and VDZ as third-line biologic therapy until December 2021 were extracted from the cohort of the Sicilian Network for Inflammatory Bowel Disease (SN-IBD). RESULTS: 143 patients (UST: n = 113; VDZ: n = 30) were included. At the end of induction, the rates of clinical response (CR) were 61.9% for UST and 60.0% for VDZ (p = 1.00), with steroid-free clinical remission (SFCR) achieved in 38.1% of patients in the UST group and 43.3% of patients in the VDZ group (p = 0.75). After 52 weeks of observation, the rates of CR were 65.9% for UST and 71.4% for VDZ (p = 0.77), while the rates of SFCR were 51.8% for UST and 57.1% for VDZ (p = 0.78). At multiple Cox proportional hazard regression model, age (HR 0.98; p = 0.04) and need for systemic steroids at baseline (HR 3.29; p = 0.003) were found to be independent predictors of treatment discontinuation. CONCLUSIONS: Both VDZ and UST showed high effectiveness as third-line biologic therapy in CD, without significant differences between them.

Severe Activity of Inflammatory Bowel Disease is a Risk Factor for Severe COVID-19.

BACKGROUND: Data from the first wave of the coronavirus disease 2019 (COVID-19) pandemic suggested that patients with inflammatory bowel disease (IBD) are not at higher risk of being infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) than the general population and that a worse prognosis is not associated with immunomodulatory drugs, with the possible exception of systemic steroids. METHODS: This retrospective, observational study included consecutive IBD patients from the Sicilian Network for Inflammatory Bowel Disease (SN-IBD) cohort who had a SARS-CoV-2 infection diagnosis (polymerase chain reaction-confirmed presence of the viral genome in a nasopharyngeal swab) during the second COVID-19 pandemic wave (September 2020 to December 2020). Data regarding demographics, IBD features and treatments, and comorbidities were analyzed in correlation with COVID-19 clinical outcomes. RESULTS: Data on 122 patients (mean age, 43.9 ±â€…16.7 years; males, 50.0%; Crohn's disease, 62.3%; ulcerative colitis, 37.7%) were reported. Twelve patients developed COVID-19-related pneumonia (9.8%), 4 (3.3%) required respiratory assistance (nonmechanical ventilation or orotracheal intubation), and 4 died (case fatality rate, 3.3%). In a multivariable analysis, age (odds ratio [OR], 1.034; 95% CI, 1.006-1.147; P = .032) and severe IBD activity (OR, 13.465; 95% CI, 1.104-164.182; P = .042) were independent predictors of COVID-19-related pneumonia, while severe IBD activity (OR, 15.359; 95% CI, 1.320-178.677; P = .030) was the only independent predictor of severe COVID-19, a composite endpoint defined as the need for respiratory assistance or death. A trend towards a protective role of tumor necrosis factor α inhibitors on pneumonia development was reported (P = .076). CONCLUSIONS: In this cohort of patients with IBD and SARS-CoV-2 infection, severe IBD activity was the only independent risk factor for severe COVID-19.

This retrospective, observational study on patients with inflammatory bowel disease and severe acute respiratory syndrome coronavirus 2 infection showed that severe inflammatory bowel disease activity was the only independent risk factor for severe coronavirus disease 2019.

Forkhead box A1 (FOXA1) is a key mediator of insulin-like growth factor I (IGF-I) activity.

The insulin-like growth factor receptor (IGF-IR) has been implicated in a number of human tumors, including breast cancer. Data from human breast tumors has demonstrated that IGF-IR is over-expressed and hyper-phosphorylated. Additionally, microarray analysis has shown that IGF-I treatment of MCF7 cells leads to a gene signature comprised of induced and repressed genes, which correlated with luminal B tumors. FOXA1, a forkhead family transcription factor, has been shown to be crucial for mammary ductal morphogenesis, similar to IGF-IR, and expressed at high levels in luminal subtype B breast tumors. Here, we investigated the relationship between FOXA1 and IGF-I action in breast cancer cells. We show that genes regulated by IGF-I are enriched for FOXA1 binding sites, and knock down of FOXA1 blocked the ability of IGF-I to regulate gene expression. IGF-I treatment of MCF7 cells increased the half-life of FOXA1 protein and this increase in half-life appeared to be dependent on canonical IGF-I signal transduction through both MAPK and AKT pathways. Finally, knock down of FOXA1 led to a decreased ability of IGF-I to induce proliferation and protect against apoptosis. Together, these results demonstrate that IGF-I can increase the stability of FOXA1 protein expression and place it as a critical mediator of IGF-I regulation of gene expression and IGF-I-mediated biological responses.

Estrogen and insulin-like growth factor-I (IGF-I) independently down-regulate critical repressors of breast cancer growth.

Although estrogen receptor alpha (ERα) and insulin-like growth factor (IGF) signaling are important for normal mammary development and breast cancer, cross-talk between these pathways, particularly at the level of transcription, remains poorly understood. We performed microarray analysis on MCF-7 breast cancer cells treated with estradiol (E2) or IGF-I for 3 or 24 h. IGF-I regulated mRNA of five to tenfold more genes than E2, and many genes were co-regulated by both ligands. Importantly, expression of these co-regulated genes correlated with poor prognosis of human breast cancer. Closer examination revealed enrichment of repressed transcripts. Interestingly, a number of potential tumor suppressors, for example, B-cell linker (BLNK), were down-regulated by IGF-I and E2. Analysis of three down-regulated genes showed that E2-mediated repression occurred independently of IGF-IR, and IGF-I-mediated repression occurred independently of ERα. However, repression by IGF-I or E2 required common kinases, such as PI3K and MEK, suggesting downstream convergence of the two pathways. In conclusion, E2 and IGF-I co-regulate a set of genes that affect breast cancer outcome. There is enrichment of repressed transcripts, and, for some genes, the down-regulation is independent at the receptor level. This may be important clinically, as tumors with active ERα and IGF-IR signaling may require co-targeting of both pathways.

Effectiveness and safety of an on-demand ferric carboxymaltose infusion strategy in patients with inflammatory bowel disease: a real world experience.

BACKGROUND: We evaluated an on-demand ferric carboxymaltose (FCM) infusion strategy in inflammatory bowel disease (IBD) patients with iron deficiency anemia (IDA). AIMS: The primary outcome was the response rate to single or multiple FCM infusions after 12 months. Secondary outcomes were the response rate to a single FCM infusion after 3 months and the FCM safety profile. METHODS: We retrospectively included 185 IBD patients who received at least one FCM infusion of 500 mg, between 2015 and 2018. FCM was administered to patients with Hb ≤10 g/dL and hypoferritinemia and repeated according to the physician's assessment. Complete response (CR) was defined as Hb ≥12 g/dL (≥13 g/dL for men) or Hb increase ≥2 g/dL. Partial response (PR) was defined as an Hb increase between 1 and 2 g/dL. A univariate analysis was performed at 3 and 12 months. RESULTS: After 12 months, the response rate was 75.1% (CR, 48.6%; PR, 26.4%; mean number of FCM infusions, 1.7 ± 1.1). In total 169/185 patients received a single FCM infusion during the first 3 months and 79.2% achieved response (CR, 56.8%; PR, 22.4%). At univariate analysis, no variable was associated with response. No adverse events were reported. CONCLUSIONS: An on-demand strategy was effective and well-tolerated in treating IDA in IBD patients.

Spondyloarthropathy in Inflammatory Bowel Disease: From Pathophysiology to Pharmacological Targets.

Spondyloarthritis (SpA) represents one of the most frequent extraintestinal manifestations of inflammatory bowel disease (IBD). Evidence of shared genetic and molecular pathways underlying both diseases is emerging, which has led to rational approaches when treating patients with concomitant diseases. Clinical efficacy of tumor necrosis factor (TNF) antagonists has been ascertained over the years, and they currently represent the cornerstone of treatment in patients with IBD and SpA, but the therapeutic armamentarium in these cases has been recently expanded. Evidence for vedolizumab is controversial, as it was associated both with improvement and development of arthralgias, while ustekinumab, the first anti-interleukin 12/23 (IL-12/23) approved for IBD, has demonstrated good efficacy, especially in peripheral arthritis, and more IL-23 inhibitors are being developed in IBD. Tofacitinib was the first Janus kinase (JAK) inhibitor to be approved in IBD, and as it demonstrated efficacy in treating ankylosing spondylitis, it may represent a good choice in axial arthritis, while more selective JAK inhibitors are yet to be approved. Unexpectedly, the first anti-IL17 that was studied in IBD (secukinumab) has shown not to be effective in treating IBD, and the role of anti-IL17 drugs in these diseases needs further investigation. Therefore, as availability of biologics and small molecules is increasing, their positioning in clinical practice is becoming more and more challenging, and multidisciplinary management needs to be implemented in both research and clinical settings in order to enhance early recognition of SpA in IBD patients, optimize treatment and ultimately improve the patients' quality of life.

Vedolizumab may be an effective option for the treatment of postoperative recurrence of Crohn's disease.

BACKGROUND: The role of Vedolizumab (VDZ) as therapeutic option for the postoperative recurrence of Crohn's disease (CD) following ileocolonic resection is unknown. AIMS: To assess the effectiveness of VDZ in this setting. METHODS: All consecutive CD patients with a baseline colonoscopy at 6-12 months from the ileocolonic resection showing postoperative recurrence (Rutgeerts score ≥i2) and treated with VDZ after the baseline colonoscopy were extracted from the cohort of the Sicilian Network for Inflammatory Bowel Diseases (SN-IBD). The primary outcome was endoscopic success, assessed at the first colonoscopy following initiation of VDZ and defined as reduction of at least one point of Rutgeerts score. The secondary outcome was clinical failure, assessed at one year and at the end of follow-up. RESULTS: Fifty-eight patients were included (mean follow-up: 24.8 ± 13.1 months). Endoscopic success was reported in 47.6% of patients. Clinical failure was reported in 19.0% of patients at one year, and in 32.8% of patients at the end of follow-up. A new resection was required in 7 patients (12.1%). CONCLUSIONS: VDZ may be an effective option for the treatment of postoperative recurrence of CD.

Blood-based prognostic biomarkers in Crohn's Disease patients on biologics: a promising tool to predict endoscopic outcomes.

OBJECTIVE: There is a growing need for biomarkers to predict therapeutic outcome in Crohn's disease (CD). MAIN OUTCOME MEASURES: The aim was to evaluate whether NLR (neutrophil-to-lymphocyte ratio), PLR (platelet-to-lymphocyte ratio), ELR (eosinophil-to-lymphocyte ratio), and ENLR (eosinophil*neutrophil-to-lymphocyte ratio), could be prognostic biomarkers of endoscopic response (ER) when starting biologics. RESEARCH DESIGN AND METHODS: Patients with CD who started biologics were enrolled. Multivariate analysis was used to evaluate whether NLR, PLR, ELR and ENLR at baseline and at w12 could predict ER (Simple Endoscopic Score for Crohn's disease [SES-CD] ≤2 or SES-CD≤2 and Rutgeerts i0-i1) after 52 weeks of treatment. Area under the curve (AUC) was calculated to find the cutoffs. RESULTS: 107 patients were included. Patients who achieved ER had significantly lower baseline NLR (p = 0.025), ELR (p = 0.013), and ENLR (p = 0.020) compared with those without ER; results after 12 weeks of treatment for ELR (p = 0.006) and ENLR (p = 0.003). AUC was 0.64 (p = 0.003), 0.67 (p = 0.006) and 0.65 (p = 0.014) for NLR, ELR and ENLR. CONCLUSIONS: Low NLR, ELR and ENLR can predict ER and could be used in clinical practice for a better management of CD patients.

Proteomic and transcriptomic profiling reveals a link between the PI3K pathway and lower estrogen-receptor (ER) levels and activity in ER+ breast cancer.

INTRODUCTION: Accumulating evidence suggests that both levels and activity of the estrogen receptor (ER) and the progesterone receptor (PR) are dramatically influenced by growth-factor receptor (GFR) signaling pathways, and that this crosstalk is a major determinant of both breast cancer progression and response to therapy. The phosphatidylinositol 3-kinase (PI3K) pathway, a key mediator of GFR signaling, is one of the most altered pathways in breast cancer. We thus examined whether deregulated PI3K signaling in luminal ER+ breast tumors is associated with ER level and activity and intrinsic molecular subtype. METHODS: We defined two independent molecular signatures of the PI3K pathway: a proteomic (reverse-phase proteomic array) PI3K signature, based on protein measurement for PI3K signaling intermediates, and a PI3K transcriptional (mRNA) signature based on the set of genes either induced or repressed by PI3K inhibitors. By using these signatures, we scored each ER+ breast tumor represented in multiple independent expression-profiling datasets (four mRNA, n = 915; one protein, n = 429) for activation of the PI3K pathway. Effects of PI3K inhibitor BEZ-235 on ER expression and activity levels and cell growth were tested by quantitative real-time PCR and cell proliferation assays. RESULTS: Within ER+ tumors, ER levels were negatively correlated with the PI3K activation scores, both at the proteomic and transcriptional levels, in all datasets examined. PI3K signature scores were also higher in ER+ tumors and cell lines of the more aggressive luminal B molecular subtype versus those of the less aggressive luminal A subtype. Notably, BEZ-235 treatment in four different ER+ cell lines increased expression of ER and ER target genes including PR, and treatment with IGF-I (which signals via PI3K) decreased expression of ER and target genes, thus further establishing an inverse functional relation between ER and PI3K. BEZ-235 had an additional effect on tamoxifen in inhibiting the growth of a number of ER+ cell lines. CONCLUSIONS: Our data suggest that luminal B tumors have hyperactive GFR/PI3K signaling associated with lower ER levels, which has been correlated with resistance to endocrine therapy. Targeting PI3K in these tumors might reverse loss of ER expression and signaling and restore hormonal sensitivity.

Effectiveness of Ustekinumab on Crohn's Disease Associated Spondyloarthropathy: Real-World Data from the Sicilian Network for Inflammatory Bowel Diseases (SN-IBD).

BACKGROUND: The effectiveness of Ustekinumab (UST) on Crohn's disease (CD)-associated spondyloarthropathy (SpA) is currently unknown. RESEARCH DESIGN AND METHODS: All consecutive CD patients with active SpA at the initiation of the treatment with UST were extracted from the cohort of the Sicilian Network for Inflammatory Bowel Diseases (SN-IBD). The primary outcome was the articular response at 8 and 24 weeks, defined as the disappearance of objective signs of arthritis (swelling and/or articular stiffness) and resolution of pain. RESULTS: Thirty CD patients with active SpA at the initiation of the treatment with UST were assessed. At 24 weeks, 13 patients (43.3%) had an articular response, including 10/18 patients (55.5%) with peripheral SpA and 3/9 patients (33.3%) with axial and peripheral SpA. No patient with axial SpA experienced an articular response. The drop of mean as Harvey-Bradshaw Index values from baseline to week 24 was higher in patients with articular response compared with non-responders (3.8 ± 2.4 vs. 1.3 ± 2.8, p = 0.02). CONCLUSIONS: Our real-world, multicentre experience showed that UST was able to obtain a response on articular symptoms in nearly half of the patients with CD and active SpA after 24 weeks of treatment.

The type I insulin-like growth factor receptor pathway: a key player in cancer therapeutic resistance.

The insulin-like growth factor (IGF) ligands stimulate cellular proliferation and survival by activating the type I insulin-like growth factor receptor (IGF-IR). As a result, the IGF signaling system is implicated in a number of cancers, including those of the breast, prostate, and lung. In addition to mitogenic and anti-apoptotic roles that may directly influence tumor development, IGF-IR also appears to be a critical determinant of response to numerous cancer therapies. This review describes the role of the IGF-IR pathway in mediating resistance to both general cytotoxic therapies, such as radiation and chemotherapy, and targeted therapies, such as tamoxifen and trastuzumab. It concludes with a description of approaches to target IGF-IR and argues that inhibition of IGF signaling, in conjunction with standard therapies, may enhance the response of cancer cells to multiple modalities.