PRL-3 as a metastasis-associated phosphatase in colorectal cancer: Mechanisms and therapeutic strategies.

Protein arginine N-methyltransferase 5 in colorectal carcinoma: Insights into mechanisms of pathogenesis and therapeutic strategies.

Colorectal Cancer

Colorectal cancer (CRC) is one of the most common tumors worldwide, with a higher rate of distant metastases than other malignancies and with regular occurrence of drug resistance. Therefore, scientists are forced to further develop novel and innovative therapeutic treatment strategies, whereby it has been discovered microorganisms, albeit linked to CRC pathogenesis, are able to act as highly selective CRC treatment agents. Consequently, researchers are increasingly focusing on bacteriotherapy as a novel therapeutic strategy with less or no side effects compared to standard cancer treatment methods. With multiple successful trials making use of various bacteria-associated mechanisms, bacteriotherapy in cancer treatment is on its way to become a promising tool in CRC targeting therapy. In this study, we describe the anti-cancer effects of bacterial therapy focusing on the treatment of CRC as well as diverse modulatory mechanisms and techniques that bacteriotherapy offers such as bacterial-related biotherapeutics including peptides, toxins, bacteriocins or the use of bacterial carriers and underlying molecular processes to target colorectal tumors.

Colorectal cancer (CRC) continues to be a predominant cause of cancer-related mortality worldwide, with existing therapies constrained by systemic toxicity, resistance, and inadequate tumor targeting. While immunotherapy has potential in specific CRC subtypes, its overall effectiveness is still limited. The cyclic GMP‒AMP synthase-stimulator of interferon genes (cGAS‒STING) pathway, an essential cytosolic DNA sensor that facilitates innate immune responses, has surfaced as a prospective target for cancer immunotherapy. Recent studies have demonstrated that it plays dual roles in CRC: on the one hand, it triggers antitumor immune responses, while on the other hand, it promotes intestinal inflammation. Accurate delivery of STING agonists made feasible by developments in nanotechnology offers novel ways to modify the TME and overcome resistance. The current understanding of the activation and function of the cGAS-STING pathway in CRC, its impact on the TME, and recent developments in STING-targeted therapeutic approaches, comprising monotherapy and combination strategies with chemotherapy, radiotherapy, and immune checkpoint inhibitors, is summarized in this review. We also review new nanomedicine approaches designed to increase STING activation. Understanding the complex roles of cGAS-STING in CRC could help guide the development of next-generation immunotherapies with improved selectivity and efficacy.

Increased neurotensin receptor-1 expression during progression of colonic adenocarcinoma

Background: Although colorectal cancer (CRC) is a potentially preventable disease, it is still one of the most common and deadliest malignancies worldwide. Despite increasing adherence to routine screening and advances in therapeutic strategies, CRC is the 1st and 3rd leading cause of cancer-related death in Puerto Rico and the United States (US), respectively. Currently, CRC screening is the primary means for prevention; however, only 40% of CRC patients are diagnosed with localized-stage disease. The fact that in 60% of CRC patients are diagnosed at more advanced, less treatable stages emphasizes the need for CRC prevention and risk stratification strategies, that other than routine screening, are still unavailable. The etiology of CRC is complex and still incompletely understood. However, environmental factors including diet, the gut microbiota, and inflammation are accepted as major contributors to colorectal carcinogenesis. It has been shown that individuals with CRC have a distinct gut microbiota, but the mechanisms by which gut bacteria exert their CRC-promoting effects remains elusive. Certain pathogenic bacterial strains carry genes encoding toxins that promote DNA damage and perpetuate inflammation, yet the association of these toxins to CRC remains poorly understood. The aim of this study was to gain insight into the mechanisms by which a subset of the gut microbiota contribute to colorectal carcinogenesis by profiling six genes encoding genotoxic and/or proinflammatory bacterial toxins in stool from individuals with and without colorectal neoplasia (adenoma and CRC). Methods: The association between the genotoxic and/or pro-inflammatory bacterial genes and CRC was examined by characterizing the toxic colonic bacterial gene profile in stool samples from healthy individuals (controls) and individuals with colorectal neoplasia (cases). Stool samples from individuals in the mainland US (n= 20) and Caribbean Hispanics (n=33) living in Puerto Rico were provided by the NCI Early Detection Research Network (http://edrn.nci.nih.gov/) and the Puerto Rico Familial Colorectal Cancer Registry (http://purificar.rcm.upr.edu/index_eng.html), respectively. Detection pks, TcPC, GelE, cnf-1, murB, and usp in stool was performed by qPCR using gene-specific primers. Associations were assessed using odds ratios. Results: Four of the six toxic genes were detected more frequently in stool samples from individuals from the US with colorectal neoplasia (controls=10; adenoma=10). Results show borderline statistical significant associations (p=0.07) with the presence of usp and >2 genes and a higher odds of colorectal neoplasia (OR=5.44 and OR=9.33, respectively). In the cohort from our Caribbean Hispanic subjects (controls=13; adenomas=12; CRC=8), individuals with the presence GelE were 8.6-times more likely to have adenomas (p=.07) and individuals with ≥ 2 of the genes were 11.3-times more likely to have CRC than individuals without these genes (p=0.04). Conclusions: Analysis with a larger number of samples will be necessary to determine a more definite association between the presence of the toxic genes in this panel in stool and colorectal neoplasia. Additional mechanistic analysis will be required to fully understand how these bacterial toxins contribute to colorectal carcinogenesis. Citation Format: Maria Gonzalez-Pons, Ramon Gómez-Moreno, Abel Baerga-Ortiz, Marcia Cruz-Correa. Association of genotoxic and/or pro-inflammatory bacterial genes to colorectal neoplasia. [abstract]. In: Proceedings of the AACR Special Conference on Colorectal Cancer: From Initiation to Outcomes; 2016 Sep 17-20; Tampa, FL. Philadelphia (PA): AACR; Cancer Res 2017;77(3 Suppl):Abstract nr A09.

Colorectal cancer (CRC) is the third most common cancer globally, causing over 900000 deaths annually. Risk factors include aging, diet, obesity, sedentary lifestyle, tobacco use, genetic predisposition, and inflammatory bowel disease. Despite current treatments, survival rates for advanced CRC remain low, highlighting the need for better therapeutic strategies. To evaluate both the clinical significance and the pathological implications of the Kinesin family member 14 (KIF14) expression within CRC specimens. Additionally, this study aims to investigate the interaction between nitidine chloride (NC) and KIF14, considering their potential as therapeutic targets. The expression of the KIF14 protein in CRC was analyzed using immunohistochemical staining. The integration of multicenter high-throughput data facilitated the calculation of the standardized mean difference (SMD) for KIF14 mRNA levels. The assessment of clinical and pathological impact was enhanced by analyzing combined receiver operating characteristic curves, along with measures of sensitivity, specificity, and likelihood ratios. Additionally, clustered regularly interspaced short palindromic repeats knockout screening for cell growth and single-cell sequencing were employed to validate the significance of KIF14 expression in CRC. Survival analysis established the prognostic value of KIF14 in CRC. The molecular mechanism of NC against CRC was elucidated through whole-genome sequencing and enrichment analysis, and molecular docking was utilized to explore the targeting affinity between NC and KIF14. KIF14 was highly expressed in 208 CRC patients. Data from 17 platforms involving 2436 CRC samples and 1320 noncancerous colorectal tissue controls indicated that KIF14 expression was significantly higher in CRC samples, with an SMD of 1.92 (95%CI: 1.49-2.35). The area under the curve was 0.94 (95%CI: 0.92-0.96), with a sensitivity of 0.85 (95%CI: 0.78-0.90) and a specificity of 0.90 (95%CI: 0.85-0.93). The positive and negative likelihood ratios were 8.38 (95%CI: 5.39-13.02) and 0.17 (95%CI: 0.11-0.26), respectively. At the single-cell level, significant overexpression of KIF14 was observed in CRC cells (P < 0.001), with 35 CRC cell lines dependent on KIF14 for growth. The K-M plots demonstrated that KIF14 possesses prognostic value in CRC patients within the GSE71187 and GSE103679 datasets (P < 0.05). Binding energy calculations indicated that KIF14 is a potential target for NC (binding energy: 10.3 kcal/mol). KIF14 promotes the growth of CRC cells and acts as an oncogenic factor, potentially serving as a therapeutic target for NC in the treatment of CRC.

Background: Colorectal cancer (CRC) remains the third most frequently diagnosed cancers in the United States. Current treatment modalities for patients with CRC include surgery, which is often followed with 5-fluorouracil (5FU) based adjuvant chemotherapy. While such treatment regimens are effective at improving disease outcomes, their clinical usefulness is often hampered due to emergence of chemotherapeutic resistance. Presence of cancer stem cells (CSCs) have been attributed towards 5FU-mediated drug resistance which subsequently leads to poor prognosis in CRC patients. In this study we investigated a novel therapeutic strategy by using metformin along with ICG-001, a Wnt signaling inhibitor, as an approach to abrogate CSC mediated chemoresistance in 5FU resistant (5FUR) and parental CRC cells, as well as CRC patient derived tumor organoids. Methods: Two 5FU resistant (5FUR)-CRC cell lines previously generated and characterized in our lab were used in this study. First, we performed genome-wide transcriptomic profiling followed by pathway enrichment analysis to identify differentially expressed genes and its associated pathways between parental and 5FUR CRC cells. Next, we determine the anti-tumor effects of metformin and ICG-001 by performing cell viability, colony formation, migration, and invasion analysis. Next, we explore the possible mechanism of action of these two drugs by performing gene and protein expression analysis of CSC, autophagy and apoptotic markers. We also evaluated the anti-tumor activity of metformin and ICG-001 in CRC patient derived tumor organoids. Results: We observed that 5FUR-CRC cells exhibited increased expression of CSC markers and increased spheroid forming ability. Genome-wide transcriptomic analysis followed by pathway analysis revealed that Wnt signaling pathway, pathways regulating pluripotency of stem cells etc. were enriched between parental and 5FUR CRC cells. These findings prompted us to use ICG-001 which selectively targets Wnt signaling along with metformin in abrogating CSC mediated chemoresistance in CRC. We observed that a combined treatment of metformin and ICG-001 exert anti-tumor activity in by decreasing cell viability (p&amp;lt;0.01), colony formation (p&amp;lt;0.001), migration (p&amp;lt;0.01), and invasion ability (p&amp;lt;0.01) in synergistic manner. We also observed that combined treatment decreases the expression of CSC markers and promote autophagy and apoptosis. In accordance with our in vitro studies, we observed that metformin and ICG-001 exhibited anti-tumor activity in patient derived CRC organoid models in combination (p&amp;lt;0.001). Conclusion: We conclude that metformin and ICG-001 act synergistically, which can be used as a therapeutic strategy to overcome 5FU mediated therapeutic resistance in CRC. Citation Format: Souvick Roy, Yinghui Zhao, Yate-Ching Yuan, Ajay Goel. Metformin and ICG-001 act synergistically to abrogate cancer stem cell-mediated chemoresistance in colorectal cancer by promoting apoptosis and autophagy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 898.

Exosomes are small extracellular vesicles (~100 nm) that are secreted by all cells and participate in cellular communication. Tumor-derived exosomes play a role in cancer progression by affecting the tumor microenvironment and establishing the pro-metastatic niche. Cancer cells are reported to have an increased release of exosomes, in addition to modulating their cargo. Therefore, blocking exosome secretion by cancer cells could halt cancer progression and be a promising novel drug-target for therapy. Global insight into the functional protein players of this process is key for development of a successful therapeutic strategy. To identify novel drug targets, Mass Spectrometry (MS)-based proteomics was performed on a unique sample set collected from 22 patients, comprising multiple fractions (tissue lysate, soluble secretome and extracellular vesicles) of matched normal and colorectal cancer (CRC) tissues (n=18) and adenomas (n=4). Available CPTAC phospho-proteomic CRC dataset was used to identify phospho-proteins that regulate the potential drug targets. Network clustering was performed using ClusterOne and gene ontology using BinGO (cytoscape). CD63 was measured using confocal microscopy. Exosome release using Coomassie stained gels and TSG101 expression using Western blot. Gene Ontology revealed deregulated pathways in normal versus cancer comparison that were linked to vesicle trafficking. Mainly, the ESCRT-pathway of the exosome biogenesis machinery was down-regulated in cancer while alternative proteins related to endocytosis and exosome release were up-regulated. Targeted data mining to the exosome biogenesis pathway revealed 12 up-regulated proteins (FC&amp;lt;1.5, p&amp;lt;0.05) and 14 proteins with increased cellular phosphorylation levels (p&amp;lt;0.05). Three upstream kinases with increased overall activity in CRC context, assessed by the INKA algorithm, were selected for further functional analysis using drugs in clinical trials or FDA-approved. To this end, two CRC cell lines were treated at IC50-correspondent dose for 16h. All three drugs caused a decrease in released exosomes after kinase inhibition, as evaluated by Coomassie staining and TSG101 levels. Intracellular immunofluorescent staining of multivesicular bodies (MVBs) by CD63, revealed increased intensity after treatment. This increase in CD63 intensity suggests an intracellular accumulation of MVBs which indicates an inability of the cell to release the exosomes. We aim to further validate the mechanisms of action underlying the inhibition of kinase-mediated exosome production and release after treatment using (phospho-)proteomics. Furthermore, we will assess its effect on exosome-mediated migration/invasion and angiogenesis. In conclusion, we describe a unique clinical dataset to identify drug targets in the exosome-release pathway, which presents a novel therapeutic strategy against CRC. Citation Format: Madalena N. Monteiro, Catarina Almeida-Marques, Meike de Wit, Valerie Dusseldorp, Logan Bishop-Currey, Sander R. Piersma, Thang V. Pham, Jaco C. Knol, Hanieh Sadeghi, Gerrit Meijer, Remond J. A. Fijneman, Angelika Hausser, Irene V. Bijnsdorp, Connie R. Jimenez. Exosome pathway inhibition as therapeutic strategy in colorectal cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr CC03-01.

Colorectal cancer (CRC) remains one of the leading causes of cancer mortality worldwide. Regarded as a heterogeneous disease, a number of biomarkers have been proposed to help in the stratification of CRC patients and to enable the selection of the best therapy for each patient towards personalized therapy. However, although the molecular mechanisms underlying the development of CRC have been elucidated, the therapeutic strategies available for these patients are still quite limited. Thus, over the last few years, a multitude of novel targets and therapeutic strategies have emerged focusing on deregulated molecules and pathways that are implicated in cell growth and survival. Particularly relevant in CRC are the activating mutations in the oncogene PIK3CA that frequently occur in concomitancy with KRAS and BRAF mutations and that lead to deregulation of the major signalling pathways PI3K and MAPK, downstream of EGFR. This review focus on the importance of the PI3K signalling in CRC development, on the current knowledge of PI3K inhibition as a therapeutic approach in CRC and on the implications PI3K signalling molecules may have as potential biomarkers and as new targets for directed therapies in CRC patients.

Simple SummaryThe survival of patients with metastatic colorectal cancer (mCRC) has been improved over the years and now reaches 30–40 months. However, few therapeutic options are available after failure of first- and second-line treatments. In fact, prognosis of chemo-refractory mCRC remains poor. Therefore, new therapeutic strategies are needed. Emerging evidence suggest that retreatment with epidermal growth factor (EGFR) inhibitors after a treatment break, in patients that obtained a clinical benefit by previous anti-EGFR, could lead to prolonged survival. The rationale beyond this “rechallenge” strategy is that after a “treatment holiday” EGFR resistant cancer cells decay, restoring the sensibility to EGFR blockade. In this review we analyze the current knowledge of retreatment with EGFR inhibitors, examine the role of novel biomarkers that can guide the appropriate selection of patients. Finally, we discuss future perspectives and on-going clinical trials.The prognosis of patients with metastatic colorectal cancer (mCRC) who progressed to the first and the second lines of treatment is poor. Thus, new therapeutic strategies are needed. During the last years, emerging evidence suggests that retreatment with anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (MAbs) in the third line of mCRC patients, that have previously obtained clinical benefit by first-line therapy with anti-EGFR MAbs plus chemotherapy, could lead to prolonged survival. The rationale beyond this “rechallenge” strategy is that, after disease progression to first line EGFR-based therapy, a treatment break from anti-EGFR drugs results in RAS mutant cancer cell decay, restoring the sensitivity of cancer cells to cetuximab and panitumumab. In fact, rechallenge treatment with anti-EGFR drugs has shown promising clinical activity, particularly in patients with plasma RAS and BRAF wild type circulating tumor DNA, as defined by liquid biopsy analysis at baseline treatment. The aim of this review is to analyze the current knowledge on rechallenge and to investigate the role of novel biomarkers that can guide the appropriate selection of patients that could benefit from this therapeutic strategy. Finally, we discuss on-going trials and future perspectives.

Advances in Hereditary Colorectal and Pancreatic Cancers

Background: Cancer is a poorly addressed major cause of morbidity and mortality in Nigeria.Aim: The study aims at analyzing the age, gender and topography of cancer in Delta State, Nigeria.Setting: The research was conducted in the State tertiary health care center, the major referral center in Delta State, Nigeria.Materials and Methods: This is a 6-year (2014-2019) descriptive retrospective study of all histologically diagnosed cancer cases in the department of Histopathology, DELSUTH.Results: Cancer accounted for 668 (28.9%) of the 2300 histologically diagnosed cases, involving 461 females and 207 males with mean ages of 48.40 and 54.14 respectively. The combined sex mean age and age range were 50.17 and 1-98 years respectively. The peak occurred in the 7th decade for males and the 6th decade for females. The most common cancers are breast (36.5%), colorectal (11.7%), prostate (8.1%) cervical (7.2), soft tissue (6%), non-melanoma skin (5.2%), ovarian (4%),metastatic (4%), gastric (2.6%), thyroid (1.8%), and salivary gland (1.4%) cancers. The peak incidence for breast and thyroid cancers; lymphomas; colorectal and cervical cancers; ovarian; and prostate cancers occurred in the 4th, 5th, 6th, 7th and 8th decades respectively.Conclusion: Cancer constitute a major disease burden, increases in incidence with age, and affects more females than males with breast, prostate, and colorectal cancers as most common cancers. Understanding the local epidemiological characteristic is fundamental to planning for proper preventive, diagnostic and therapeutic strategies.

&lt;div&gt;Abstract&lt;p&gt;Colorectal cancers harboring &lt;i&gt;KRAS&lt;/i&gt; or &lt;i&gt;BRAF&lt;/i&gt; mutations are refractory to current targeted therapies. Using data from a high-throughput drug screen, we have developed a novel therapeutic strategy that targets the apoptotic machinery using the BCL-2 family inhibitor ABT-263 (navitoclax) in combination with a TORC1/2 inhibitor, AZD8055. This combination leads to efficient apoptosis specifically in &lt;i&gt;KRAS&lt;/i&gt;- and &lt;i&gt;BRAF&lt;/i&gt;-mutant but not wild-type (WT) colorectal cancer cells. This specific susceptibility results from TORC1/2 inhibition leading to suppression of MCL-1 expression in mutant, but not WT, colorectal cancers, leading to abrogation of BIM/MCL-1 complexes. This combination strategy leads to tumor regressions in both &lt;i&gt;KRAS&lt;/i&gt;-mutant colorectal cancer xenograft and genetically engineered mouse models of colorectal cancer, but not in the corresponding &lt;i&gt;KRAS&lt;/i&gt;-WT colorectal cancer models. These data suggest that the combination of BCL-2/BCL-XL inhibitors with TORC1/2 inhibitors constitutes a promising targeted therapy strategy to treat these recalcitrant cancers.&lt;/p&gt;&lt;p&gt;&lt;b&gt;Significance:&lt;/b&gt; Effective targeted therapies directed against colorectal cancer with activating mutations in &lt;i&gt;KRAS&lt;/i&gt; remain elusive. We have leveraged drug-screen data from a large panel of human colorectal cancers to uncover an effective, rational targeted therapy strategy that has preferential activity in colorectal cancers with &lt;i&gt;KRAS&lt;/i&gt; or &lt;i&gt;BRAF&lt;/i&gt; mutations. This combination may be developed for clinical testing. &lt;i&gt;Cancer Discov; 4(1); 42–52. ©2013 AACR&lt;/i&gt;.&lt;/p&gt;&lt;p&gt;See related commentary by Russo et al., p. 19&lt;/p&gt;&lt;p&gt;This article is highlighted in the In This Issue feature, p. 1&lt;/p&gt;&lt;/div&gt;

&lt;div&gt;Abstract&lt;p&gt;Colorectal cancers harboring &lt;i&gt;KRAS&lt;/i&gt; or &lt;i&gt;BRAF&lt;/i&gt; mutations are refractory to current targeted therapies. Using data from a high-throughput drug screen, we have developed a novel therapeutic strategy that targets the apoptotic machinery using the BCL-2 family inhibitor ABT-263 (navitoclax) in combination with a TORC1/2 inhibitor, AZD8055. This combination leads to efficient apoptosis specifically in &lt;i&gt;KRAS&lt;/i&gt;- and &lt;i&gt;BRAF&lt;/i&gt;-mutant but not wild-type (WT) colorectal cancer cells. This specific susceptibility results from TORC1/2 inhibition leading to suppression of MCL-1 expression in mutant, but not WT, colorectal cancers, leading to abrogation of BIM/MCL-1 complexes. This combination strategy leads to tumor regressions in both &lt;i&gt;KRAS&lt;/i&gt;-mutant colorectal cancer xenograft and genetically engineered mouse models of colorectal cancer, but not in the corresponding &lt;i&gt;KRAS&lt;/i&gt;-WT colorectal cancer models. These data suggest that the combination of BCL-2/BCL-XL inhibitors with TORC1/2 inhibitors constitutes a promising targeted therapy strategy to treat these recalcitrant cancers.&lt;/p&gt;&lt;p&gt;&lt;b&gt;Significance:&lt;/b&gt; Effective targeted therapies directed against colorectal cancer with activating mutations in &lt;i&gt;KRAS&lt;/i&gt; remain elusive. We have leveraged drug-screen data from a large panel of human colorectal cancers to uncover an effective, rational targeted therapy strategy that has preferential activity in colorectal cancers with &lt;i&gt;KRAS&lt;/i&gt; or &lt;i&gt;BRAF&lt;/i&gt; mutations. This combination may be developed for clinical testing. &lt;i&gt;Cancer Discov; 4(1); 42–52. ©2013 AACR&lt;/i&gt;.&lt;/p&gt;&lt;p&gt;See related commentary by Russo et al., p. 19&lt;/p&gt;&lt;p&gt;This article is highlighted in the In This Issue feature, p. 1&lt;/p&gt;&lt;/div&gt;