The impact of panitumumab treatment on survival and quality of life in patients with RAS wild-type metastatic colorectal cancer

Impact of Systemic Treatments on Outcomes and Quality of Life in Patients with RAS-Positive Stage IV Colorectal Cancer: A Systematic Review

This systematic review critically evaluates the impact of systemic treatments on outcomes and quality of life (QoL) in patients with RAS-positive stage IV colorectal cancer, with studies published up to December 2023 across PubMed, Scopus, and Web of Science. From an initial pool of 1345 articles, 11 relevant studies were selected for inclusion, encompassing a diverse range of systemic treatments, including panitumumab combined with FOLFOX4 and FOLFIRI, irinotecan paired with panitumumab, regorafenib followed by cetuximab ± irinotecan and vice versa, and panitumumab as a maintenance therapy post-induction. Patient demographics predominantly included middle-aged to elderly individuals, with a slight male predominance. Racial composition, where reported, showed a majority of Caucasian participants, highlighting the need for broader demographic inclusivity in future research. Key findings revealed that the addition of panitumumab to chemotherapy (FOLFOX4 or FOLFIRI) did not significantly compromise QoL while notably improving disease-free survival, with baseline EQ-5D HSI mean scores ranging from 0.76 to 0.78 and VAS mean scores from 70.1 to 74.1. Improvements in FACT-C scores and EQ-5D Index scores particularly favored panitumumab plus best supportive care in KRAS wild-type mCRC, with early dropout rates of 38-42% for panitumumab + BSC. Notably, cetuximab + FOLFIRI was associated with a median survival of 25.7 months versus 16.4 months for FOLFIRI alone, emphasizing the potential benefits of integrating targeted therapies with chemotherapy. In conclusion, the review underscores the significant impact of systemic treatments, particularly targeted therapies and their combinations with chemotherapy, on survival outcomes and QoL in patients with RAS-positive stage IV colorectal cancer, and the need for personalized treatment.

Targeted Inhibitors of EGFR: Structure, Biology, Biomarkers, and Clinical Applications

Members of the EGFR family of tyrosine kinase receptors are major regulators of cellular proliferation, differentiation, and survival. In humans, abnormal activation of EGFR is associated with the development and progression of many cancer types, which makes it an attractive target for molecular-guided therapy. Two classes of EGFR-targeted cancer therapeutics include monoclonal antibodies (mAbs), which bind to the extracellular domain of EGFR, and tyrosine kinase inhibitors (TKIs), which mostly target the intracellular part of EGFR and inhibit its activity in molecular signaling. While EGFR-specific mAbs and three generations of TKIs have demonstrated clinical efficacy in various settings, molecular evolution of tumors leads to apparent and sometimes inevitable resistance to current therapeutics, which highlights the need for deeper research in this field. Here, we tried to provide a comprehensive and systematic overview of the rationale, molecular mechanisms, and clinical significance of the current EGFR-targeting drugs, highlighting potential candidate molecules in development. We summarized the underlying mechanisms of resistance and available personalized predictive approaches that may lead to improved efficacy of EGFR-targeted therapies. We also discuss recent developments and the use of specific therapeutic strategies, such as multi-targeting agents and combination therapies, for overcoming cancer resistance to EGFR-specific drugs.

Improved Production of Anti-FGF-2 Nanobody Using Pichia pastoris and Its Effect on Antiproliferation of Keratinocytes and Alleviation of Psoriasis

Fibroblast growth factor 2 (FGF-2) is not only an angiogenic factor, but also a mitogen for epidermal keratinocytes. FGF-2 has been shown to be positively immunoreactive in the basal layer of psoriatic lesions. In previous work, we used the Escherichia coli (E. coli) expression system to biosynthesize a biologically active anti-FGF-2 nanobody (Nb) screened by phage display technology, but the low yield limited its clinical application. In this study, we aimed to increase the yield of anti-FGF-2 Nb, and evaluate its therapeutic potential for psoriasis by inhibiting FGF-2-mediated mitogenic signaling in psoriatic epidermal keratinocytes. We demonstrated a 16-fold improvement in the yield of anti-FGF-2 Nb produced in the Pichia pastoris (P. pastoris) compared to the  E. coli expression system. In vitro, the FGF-2-induced HaCaT cell model (FHCM) was established to mimic the key feature of keratinocyte overproliferation in psoriasis. Anti-FGF-2 Nb was able to effectively inhibit the proliferation and migration of FHCM. In vivo, anti-FGF-2 Nb attenuated the severity of imiquimod (IMQ)-induced psoriatic lesions in mice, and also improved the inflammatory microenvironment by inhibiting the secretion of inflammatory cytokines (IL-1β, IL-6, IL-23, and TNF-α), chemokines (CXCL1 and CCL20), and neutrophil infiltration in skin lesions. These were mainly related to the suppression of FGF-2-mediated mitogenic signaling in psoriatic keratinocytes. In conclusion, we have improved the production of anti-FGF-2 Nb and demonstrated the modality of attenuating the abnormal proliferative behavior of psoriatic keratinocytes by inhibiting FGF-2-mediated mitogenic signaling, which offers the possibility of treating psoriasis.

A Review of 10-Year Survivability of Immunotherapy in the Management of Colon Cancer

Colon cancer is one of the most common cancers in the United States of America. In addition to conventional treatment approaches such as surgery, chemotherapy, and radiation for colorectal cancer, immunotherapy has gained recognition over the past few years. However, its effectiveness in colorectal cancer treatment is controversial. Our study investigates the survival and progression-free rates of immunotherapy for different types of colorectal cancer over the last 10 years. We conducted literature reviews from various clinical trials and research studies to evaluate immunotherapy's role in colorectal cancer treatment. We also investigated how it affects clinical outcomes. We discovered a range of effective immunotherapy approaches targeting various growth factors and signaling pathways. These modalities include monoclonal antibodies aimed at growth factors such as epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), human epidermal growth factor receptor 2 (HER2), and downstream signaling pathways such as mitogen-activated protein kinase (MAPK), kirsten rat sarcoma viral oncogene (KRAS), B-raf proto-oncogene, serine/threonine kinase (BRAF), and phosphatase and tensin homolog (PTEN). Additionally, we identified immune checkpoint inhibitors, such as cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) inhibitors and programmed cell death ligand 1 (PD-L1) inhibitors, as well as target therapy and adoptive cell therapy as promising immunotherapeutic options. Nevertheless, the application of immunotherapy remains highly limited due to various factors influencing survival and progression-free rates, including tumor microenvironment, microsatellite instability, immune checkpoint expression, and gut microbiome. Additionally, its effectiveness is restricted to a small subgroup of patients, accompanied by side effects and the development of drug resistance mechanisms. To unlock its full potential, further clinical trials and research on molecular pathways in colorectal cancer are imperative. This will ultimately enhance drug discovery success and lead to more effective clinical management approaches.

S. M, Birudala G, Jamous YF, Alshargi O, Kotha KK, Sudhan HH, Mani RR, Muthumanickam A, Niranjan D, Jain NK, Agrawal A, Jadon AS, Mayasa V, Jha NK, Kolesarova A, Slama P, Roychoudhury S. Reactive oxygen species mediated apoptotic death of colon cancer cells: therapeutic potential of plant derived alkaloids

Colorectal cancer (CRC) is one of the most deaths causing diseases worldwide. Several risk factors including hormones like insulin and insulin like growth factors (e.g., IGF-1) have been considered responsible for growth and progression of colon cancer. Though there is a huge advancement in the available screening as well as treatment techniques for CRC. There is no significant decrease in the mortality of cancer patients. Moreover, the current treatment approaches for CRC are associated with serious challenges like drug resistance and cancer re-growth. Given the severity of the disease, there is an urgent need for novel therapeutic agents with ideal characteristics. Several pieces of evidence suggested that natural products, specifically medicinal plants, and derived phytochemicals may serve as potential sources for novel drug discovery for various diseases including cancer. On the other hand, cancer cells like colon cancer require a high basal level of reactive oxygen species (ROS) to maintain its own cellular functions. However, excess production of intracellular ROS leads to cancer cell death via disturbing cellular redox homeostasis. Therefore, medicinal plants and derived phytocompounds that can enhance the intracellular ROS and induce apoptotic cell death in cancer cells via modulating various molecular targets including IGF-1 could be potential therapeutic agents. Alkaloids form a major class of such phytoconstituents that can play a key role in cancer prevention. Moreover, several preclinical and clinical studies have also evidenced that these compounds show potent anti-colon cancer effects and exhibit negligible toxicity towards the normal cells. Hence, the present evidence-based study aimed to provide an update on various alkaloids that have been reported to induce ROS-mediated apoptosis in colon cancer cells via targeting various cellular components including hormones and growth factors, which play a role in metastasis, angiogenesis, proliferation, and invasion. This study also provides an individual account on each such alkaloid that underwent clinical trials either alone or in combination with other clinical drugs. In addition, various classes of phytochemicals that induce ROS-mediated cell death in different kinds of cancers including colon cancer are discussed.

Real-world treatment patterns and clinical outcomes for chemotherapy-based regimens in first-line MSI-H/dMMR metastatic colorectal cancer

MICRO ABSTRACT

This retrospective observational study assessed real-world treatment patterns and clinical outcomes among first-line MSI-H/dMMR metastatic colorectal cancer patients. Of 150 patients in the study cohort, 38.7% were treated with chemotherapy and 61.3% with chemotherapy + EGFR/VEGF inhibitor (EGFRi/VEGFi). Clinical outcomes were better among patients who received chemotherapy + EGFR/VEGF inhibitor than those who received chemotherapy.

INTRODUCTION

Prior to pembrolizumab approval in first-line (1L) treatment of MSI-H/dMMR metastatic colorectal cancer (mCRC), patients were managed with chemotherapy with or without an EGFRi or VEGFi, agnostic of biomarker testing or mutation status. This study assessed real-world treatment patterns and clinical outcomes among 1L MSI-H/dMMR mCRC patients treated with standard of care (SOC).

PATIENTS AND METHODS

Retrospective observational evaluation of patients ≥18 years diagnosed with stage IV MSI-H/dMMR mCRC who received community-based oncology care. Eligible patients were identified (01-Jun-2017 - 29-Feb-2020) and followed longitudinally until 31-Aug-2020/the last patient record/date of death. Descriptive statistics and Kaplan-Meier analyses were conducted.

RESULTS

Of 150 1L MSI-H/dMMR mCRC patients, 38.7% were treated with chemotherapy and 61.3% with chemotherapy + EGFRi/VEGFi. Accounting for censoring, the overall median real-world time to treatment discontinuation (95% CI) was 5.3 (4.4, 5.8) months; 3.0 (2.1, 4.4) and 6.2 (5.5, 7.6) months in the chemotherapy and chemotherapy + EGFRi/VEGFi cohorts, respectively. The combined median overall survival was 27.7 (23.2, not reached [NR]) months; 25.3 (14.5, NR) and 29.8 (23.2, NR) months in the chemotherapy and chemotherapy + EGFRi/VEGFi cohorts, respectively. The overall median real-world progression-free survival was 6.8 (5.3, 7.8) months; 4.2 (2.8, 6.1) and 7.7 (6.1, 10.2) months in the chemotherapy and chemotherapy + EGFRi/VEGFi cohorts, respectively.

CONCLUSIONS

1L MSI-H/dMMR mCRC patients receiving chemotherapy with EGFRi/VEGFi had better outcomes than those receiving only chemotherapy. An unmet need and opportunity to improve outcomes exists in this population that may be addressed by newer treatments like immunotherapies.

Quality of life with encorafenib plus cetuximab with or without binimetinib treatment in patients with BRAF V600E-mutant metastatic colorectal cancer: patient-reported outcomes from BEACON CRC

Background

In the BEACON CRC study (NCT02928224), encorafenib plus cetuximab with binimetinib {9.3 versus 5.9 months; hazard ratio (HR) [95% confidence interval (CI)]: 0.60 [0.47-0.75]} or without binimetinib [9.3 versus 5.9 months; HR (95% CI): 0.61 (0.48-0.77)] significantly improved overall survival (OS) compared with the previous standard of care (control) in patients with BRAF V600E metastatic colorectal cancer (mCRC). Quality of life (QoL) was a secondary endpoint, assessed using validated instruments.

Patients and methods

BEACON CRC was a randomized, open-label, phase III study comparing encorafenib plus cetuximab with or without binimetinib and the investigator’s choice of irinotecan plus cetuximab or FOLFIRI plus cetuximab (chemotherapy control) in patients with previously treated BRAF V600E mCRC. Patient-reported QoL assessments included the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC) and Functional Assessment of Cancer Therapy—Colorectal (FACT-C). The primary outcome for these tools was time to definitive 10% deterioration.

Results

Encorafenib plus cetuximab, both with and without binimetinib, was associated with longer median times to definitive 10% deterioration versus the control group in the EORTC Global Health Status scale [HR (95% CI): 0.65 (0.52-0.80) versus 0.61 (0.49-0.75), respectively] and the FACT-C functional well-being subscale [HR (95% CI): 0.62 (0.50-0.76) versus 0.58 (0.47-0.72), respectively]. Consistent results were observed across all subscales of the EORTC and FACT-C instruments. QoL was generally maintained during treatment for the global EORTC and FACT-C scales.

Conclusions

In addition to improving OS, encorafenib plus cetuximab with or without binimetinib delays QoL decline in previously treated patients with BRAF V600E-mutant mCRC.

•

BEACON CRC compares encorafenib + cetuximab ± binimetinib to chemotherapy in previously treated BRAF V600E mCRC.

•

Encorafenib + cetuximab had longer time to 10% deterioration versus control in QoL and functional well-being scales.

•

Encorafenib + cetuximab ± binimetinib delays QoL decline in previously treated patients with BRAF V600E mCRC.

Inoperable de novo metastatic colorectal cancer with primary tumour in situ: Evaluating discordant responses to upfront systemic therapy of the primary tumours and metastatic sites and complications arising from primary tumours (experiences from an Irish Cancer Centre)

Systemic therapy is the mainstay of treatment for de novo metastatic colorectal cancer (mCRC). Heterogeneity between primary tumours and metastases may lead to discordant responses to systemic therapy at these sites. The aim of the present study was to examine these discrepancies and to evaluate the rates of complications arising from the primary tumour and the strategies employed to manage these complications. Electronic medical records were screened for patients eligible for data analysis between January 1st, 2014 and December 31st, 2019. All patients diagnosed with de novo mCRC with primary tumour in situ at the time of initial systemic therapy were included in data analysis. Responses in primary tumour and metastatic sites (according to the Response Evaluation Criteria In Solid Tumours v1.1), discrepancies in these responses and rates of complications arising from primary tumours were assessed along with patient, pathological or molecular factors that may be associated with these discrepant responses or primary tumour complications. A total of 50 patients were identified (median age, 62 years). Right-colon, left-colon and rectal primary tumours comprised 34, 44 and 22% of CRC cases, respectively. All patients received 5-fluorouracil-based chemotherapy (either alone or in combination with oxaliplatin or irinotecan). Disease response (DR), stable disease (SD) and progressive disease (PD) were observed as the first response to systemic therapy in 24, 62 and 12% of primary tumours and in 36, 18 and 44% of metastatic sites, respectively. Only 36% of patients demonstrated concordant responses between the primary tumours and metastases, while the remaining 62% demonstrated discordant responses between the primary tumour and distant metastases (22% had DR with SD; 36% had DR or SD with PD; and 4% had PD with SD in the primary tumour and metastases, respectively). Restaging images were not available for 2% of the patients. Approximately 30% of patients developed complications from primary tumours, including bowel obstruction (6.12%), perforation (6%), rectal pain (6%) and rectal bleeding (10%). Approximately 10% of patients underwent palliative stoma creation. Additionally, 12% required palliative radiotherapy to the primary tumour (due to localized complications arising from the tumour). Discordant responses to systemic therapy between primary tumours and metastases occurred in 60% of patients with de novo mCRC (with primary tumour in situ at the time of first systemic therapy). The observations of the present study have potential implications for molecular tissue analysis to help guide systemic therapy. Tissue from metastatic sites may be preferable to confirm biomarker status in mCRC based on this study.

Triazole-estradiol analogs: A potential cancer therapeutic targeting ovarian and colorectal cancer

1,2,3-triazoles have continuously shown effectiveness as biologically active systems towards various cancers, and when used in combination with steroid skeletons as a carrier, which can act as a drug delivery system, allows for a creation of a novel set of analogs that may be useful as a pharmacophore leading to a potential treatment option for cancer. A common molecular target for cancer inhibition is that of the Epidermal Growth Factor Receptor/Mitogen Activated Protein Kinase pathways, as inhibition of these proteins is associated with a decrease in cell viability. Estradiol-Triazole analogs were thus designed using a molecular modeling approach. Thirteen of the high scoring analogs were then synthesized and tested in-vitro on an ovarian cancer cell line (A2780) and colorectal cancer cell line (HT-29). The most active compound, Fz25, shows low micromolar activity in both the ovarian (15.29 ± 2.19 µM) and colorectal lines (15.98 ± 0.39 µM). Mechanism of action studies proved that Fz25 moderately arrests cells in the G1 phase of the cell cycle, specifically inhibiting STAT3 in both cell lines. Additionally, Fz57 shows activity in the colorectal line (24.19 ± 1.37 µM). Inhibition studies in both cell lines show inhibition against various proteins in the EGFR pathway, namely EGFR, STAT3, ERK, and mTOR. To further study their effects as therapeutics, Fz25 and Fz57 were studied against drug efflux proteins, which are associated with drug resistance, and were found to inhibit the ABC transporter P-glycoprotein. We can conclude that these estradiol-triazole analogs provide a key for future studies targeting protein inhibition and drug resistance in cancer.

Personalized Immunotherapy in Colorectal Cancers: Where Do We Stand?

Colorectal cancer (CRC) is the second leading cause of cancer death in the world. Immunotherapy using monoclonal antibodies, immune-checkpoint inhibitors, adoptive cell therapy, and cancer vaccines has raised great hopes for treating poor prognosis metastatic CRCs that are resistant to the conventional therapies. However, high inter-tumor and intra-tumor heterogeneity hinder the success of immunotherapy in CRC. Patients with a similar tumor phenotype respond differently to the same immunotherapy regimen. Mutation-based classification, molecular subtyping, and immunoscoring of CRCs facilitated the multi-aspect grouping of CRC patients and improved immunotherapy. Personalized immunotherapy using tumor-specific neoantigens provides the opportunity to consider each patient as an independent group deserving of individualized immunotherapy. In the recent decade, the development of sequencing and multi-omics techniques has helped us classify patients more precisely. The expansion of such advanced techniques along with the neoantigen-based immunotherapy could herald a new era in treating heterogeneous tumors such as CRC. In this review article, we provided the latest findings in immunotherapy of CRC. We elaborated on the heterogeneity of CRC patients as a bottleneck of CRC immunotherapy and reviewed the latest advances in personalized immunotherapy to overcome CRC heterogeneity.

A review on epidermal growth factor receptor's role in breast and non-small cell lung cancer

Epithelial growth factor receptor (EGFR) is a cell surface transmembrane receptor that mediates the tyrosine signaling pathway to carry the extracellular messages inside the cell and thereby alter the function of nucleus. This leads to the generation of various protein products to up or downregulate the cellular function. It is encoded by cell erythroblastosis virus oncogene B1, so called C-erb B1/ERBB2/HER-2 gene that acts as a proto-oncogene. It belongs to the HER-2 receptor-family in breast cancer and responds best with anti-Herceptin therapy (anti-tyrosine kinase monoclonal antibody). HER-2 positive breast cancer patient exhibits worse prognosis without Herceptin therapy. Similar incidence and prognosis are reported in other epithelial neoplasms like EGFR + lung non-small cell carcinoma and glioblastoma (grade IV brain glial tumor). Present study highlights the role and connectivity of EGF with various cancers via signaling pathways, cell surface receptors mechanism, macromolecules, mitochondrial genes and neoplasm. Present study describes the EGFR associated gene expression profiling (in breast cancer and NSCLC), relation between mitrochondrial genes and carcinoma, and several in vitro and in vivo models to screen the synergistic effect of various combination treatments. According to this study, although clinical studies including targeted treatments, immunotherapies, radiotherapy, TKi-EGFR combined targeted therapy have been carried out to investigate the synergism of combination therapy; however still there is a gap to apply the scenarios of experimental and clinical studies for further developments. This review will give an idea about the transition from experimental to most advanced clinical studies with different combination drug strategies to treat cancer.

Panitumumab: A Review of Clinical Pharmacokinetic and Pharmacology Properties After Over a Decade of Experience in Patients with Solid Tumors

Panitumumab is a fully human monoclonal antibody that binds to the epidermal growth factor receptor (EGFR), thereby inhibiting the growth and survival of tumors expressing EGFR. Panitumumab received approval in the USA in 2006 for the treatment of wild-type RAS (defined as wild-type in both KRAS and NRAS) metastatic colorectal cancer. Over the last 10 years, the pharmacokinetic and pharmacodynamic profile of panitumumab has been studied to further evaluate its safety, efficacy, and optimal dosing regimen. In this review, we summarize the key clinical pharmacokinetic and pharmacology data for panitumumab, and considerations for its use in special populations. Panitumumab has a nonlinear pharmacokinetic profile and its approved dosing regimen (6 mg/kg every 2 weeks) is based on body weight; dose adjustments are not needed based on sex, age, or renal or hepatic impairment. Drug interactions do not occur when panitumumab is combined with chemotherapy drugs including irinotecan, paclitaxel, and carboplatin. The level of tumor EGFR expression was found to have no effect on panitumumab pharmacokinetics or efficacy. The incidence of anti-panitumumab antibodies is low; when anti-panitumumab antibodies are produced, they do not affect the efficacy, safety, or pharmacokinetics of panitumumab. In summary, the pharmacokinetic and pharmacodynamic profile of panitumumab is well suited for standard dosing, and the approved body weight-based dosing regimen maintains efficacy and safety in the treatment of wild-type RAS metastatic colorectal cancer across a broad range of patients.

Targeting EML4-ALK gene fusion variant 3 in thyroid cancer

Finding targetable gene fusions can expand the limited treatment options in radioactive iodine-refractory (RAI-r) thyroid cancer. To that end, we established a novel cell line 'JVE404' derived from an advanced RAI-r papillary thyroid cancer (PTC) patient, harboring an EML4-ALK gene fusion variant 3 (v3). Different EML4-ALK gene fusions can have different clinical repercussions. JVE404 cells were evaluated for cell viability and cell signaling in response to ALK inhibitors crizotinib, ceritinib and lorlatinib, in parallel to the patient's treatment. He received, after first-line lenvatinib, crizotinib (Drug Rediscovery Protocol (DRUP) trial), and lorlatinib (compassionate use). In vitro treatment with crizotinib or ceritinib decreased viability in JVE404, but most potently and significantly only with lorlatinib. Western blot analysis showed a near total decrease of 99% and 89%, respectively, in pALK and pERK expression levels in JVE404 cells with lorlatinib, in contrast to remaining signal intensities of a half and a third of control, respectively, with crizotinib. The patient had a 6-month lasting stable disease on crizotinib, but progressive disease occurred, including the finding of cerebral metastases, at 8 months. With lorlatinib, partial response, including clinical cerebral activity, was already achieved at 11 weeks' use and ongoing partial response at 7 months. To our best knowledge, this is the first reported case describing a patient-specific targeted treatment with lorlatinib based on an EML4-ALK gene fusion v3 in a thyroid cancer patient, and own cancer cell line. Tumor-agnostic targeted therapy may provide valuable treatment options in personalized medicine.

Recent Advances in Our Knowledge of mCRC Tumor Biology and Genetics: A Focus on Targeted Therapy Development

Metastatic colorectal cancer (mCRC) remains a highly lethal malignancy although considerable progress has resulted from characterizing molecular alterations such as RAS mutation status and extent of microsatellite instability (MSI) to guide optimal use of available therapies. The availability of gene expression profiling, next generation sequencing technologies, proteomics analysis and other technologies provides high resolution information on individual tumors, including metastatic lesions to better define intra-tumor and inter-tumor heterogeneity. Recent literature applying this information to further customize personalized therapies is reviewed. Current biomarker-based stratification used to select optimal therapy that is personalized to the mutation profile of individual tumors is described. Recent literature using whole exome sequencing of metastatic lesions and primary CRC tumors and other advanced technologies to more fully elucidate the tumor biology specific to mCRC sub-types and to develop more precise therapies that improve outcomes is also reviewed.

Modular Reorganization of Signaling Networks during the Development of Colon Adenoma and Carcinoma

Network science is an emerging tool in systems biology and oncology, providing novel, system-level insight into the development of cancer. The aim of this project was to study the signaling networks in the process of oncogenesis to explore the adaptive mechanisms taking part in the cancerous transformation of healthy cells. For this purpose, colon cancer proved to be an excellent candidate as the preliminary phase, and adenoma has a long evolution time. In our work, transcriptomic data have been collected from normal colon, colon adenoma, and colon cancer samples to calculating link (i.e., network edge) weights as approximative proxies for protein abundances, and link weights were included in the Human Cancer Signaling Network. Here we show that the adenoma phase clearly differs from the normal and cancer states in terms of a more scattered link weight distribution and enlarged network diameter. Modular analysis shows the rearrangement of the apoptosis- and the cell-cycle-related modules, whose pathway enrichment analysis supports the relevance of targeted therapy. Our work enriches the system-wide assessment of cancer development, showing specific changes for the adenoma state.

Monoclonal antibodies and chimeric antigen receptor (CAR) T cells in the treatment of colorectal cancer

Colorectal cancer (CRC) is the third most common cancer and the second leading cause of cancer deaths worldwide. Besides common therapeutic approaches, such as surgery, chemotherapy, and radiotherapy, novel therapeutic approaches, including immunotherapy, have been an advent in CRC treatment. The immunotherapy approaches try to elicit patients` immune responses against tumor cells to eradicate the tumor. Monoclonal antibodies (mAbs) and chimeric antigen receptor (CAR) T cells are two branches of cancer immunotherapy. MAbs demonstrate the great ability to completely recognize cancer cell-surface receptors and blockade proliferative or inhibitory pathways. On the other hand, T cell activation by genetically engineered CAR receptor via the TCR/CD3 and costimulatory domains can induce potent immune responses against specific tumor-associated antigens (TAAs). Both of these approaches have beneficial anti-tumor effects on CRC. Herein, we review the different mAbs against various pathways and their applications in clinical trials, the different types of CAR-T cells, various specific CAR-T cells against TAAs, and their clinical use in CRC treatment.

Redefining Colorectal Cancer by Tumor Biology

Colorectal cancer treatment has undergone a paradigm shift. We no longer see this disease as a singular, anatomic tumor type but rather a set of disease subgroups. Largely because of a better understanding of cancer biology and the introduction and integration of molecular biomarkers-the premise of precision therapy-we are beginning to direct treatments toward the right tumor target(s) in the right patients. The field of molecular profiling is continually evolving, and new biomarkers are constantly being discovered that have investigational, therapeutic, and/or prognostic implications-negative or positive. To date, only a few biomarkers have sufficient actionable, clinical implication to earn international guideline-recommended routine testing. Hence, it is vital that the treating oncologist should know which biomarkers to assess, when in the treatment course to test for them, and how the test is to be done. Correct interpretation of profiling results is imperative. Herein, we focus on international guideline-recommended mutation testing for patients prior to their colorectal cancer treatment initiation. The clinical applications of circulating tumor DNA (ctDNA) in patients with metastatic disease, based on our current knowledge and capabilities, are also addressed.

Regorafenib suppresses epidermal growth factor receptor signaling-modulated progression of colorectal cancer

Active epidermal growth factor receptors (EGFR) signaling mediates the progression of colorectal cancer (CRC) through activation of downstream kinases and transcription factors. The increased expression of EGFR was associated with worse prognosis in patients with metastatic CRC (mCRC). Regorafenib, the oral kinase inhibitor approved for the treatment of mCRC, has been shown to reduce activation of downstream kinases of EGFR signal pathway in hepatocellular carcinoma and osteosarcoma. However, whether EGFR inactivation was participates in regorafenib-inhibited progression of CRC still remaining ambiguous. The major purpose of present study was to verify effect of regorafenib on EGFR signaling-mediated progression of CRC. Here, we investigated the effect of regorafenib or erlotinib (EGFR inhibitor) on tumor cell growth, invasion ability, apoptotic, and EGFR signal transduction in CRC in vitro and in vivo. Our results indicated regorafenib reduced EGF-induced EGFR and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activity. Both regorafenib and erlotinib significantly reduced cell invasion ability, activation of protein kinase C-δ (PKCδ), protein kinase B (AKT), extracellular signal-regulated kinases (ERK), and NF-κB. Regorafenib can trigger the inhibition of tumor cell growth and the induction of apoptosis through extrinsic/intrinsic apoptosis pathways. In addition, the expression of NF-κB-mediated proteins involved in tumor progression was also suppressed by regorafenib treatment. Taken together, regorafenib acts as a inhibitor of EGFR signaling that attenuated the activation of EGFR and EGFR related downstream signaling cascades in CRC. Our results suggested that the suppression of EGFR signaling was associated with regorafenib-inhibited progression of CRC.

Clinical Multigene Panel Sequencing Identifies Distinct Mutational Association Patterns in Metastatic Colorectal Cancer

Extensive molecular characterization of human colorectal cancer (CRC) via Next Generation Sequencing (NGS) indicated that genetic or epigenetic dysregulation of a relevant, but limited, number of molecular pathways typically occurs in this tumor. The molecular picture of the disease is significantly complicated by the frequent occurrence of individually rare genetic aberrations, which expand tumor heterogeneity. Inter- and intratumor molecular heterogeneity is very likely responsible for the remarkable individual variability in the response to conventional and target-driven first-line therapies, in metastatic CRC (mCRC) patients, whose median overall survival remains unsatisfactory. Implementation of an extensive molecular characterization of mCRC in the clinical routine does not yet appear feasible on a large scale, while multigene panel sequencing of most commonly mutated oncogene/oncosuppressor hotspots is more easily achievable. Here, we report that clinical multigene panel sequencing performed for anti-EGFR therapy predictive purposes in 639 formalin-fixed paraffin-embedded (FFPE) mCRC specimens revealed previously unknown pairwise mutation associations and a high proportion of cases carrying actionable gene mutations. Most importantly, a simple principal component analysis directed the delineation of a new molecular stratification of mCRC patients in eight groups characterized by non-random, specific mutational association patterns (MAPs), aggregating samples with similar biology. These data were validated on a The Cancer Genome Atlas (TCGA) CRC dataset. The proposed stratification may provide great opportunities to direct more informed therapeutic decisions in the majority of mCRC cases.

Circulating tumor DNA applications in monitoring the treatment of metastatic colorectal cancer patients

Colorectal cancer is the third most common cancer worldwide. New cancer treatment strategies such as monoclonal antibodies against growth factor and angiogenesis receptors have improved the overall survival (OS) and progression-free survival (PFS) in metastatic colorectal cancer (mCRC) patients. However, acquired resistance could happen after these therapies. Circulating tumor DNA (ctDNA) is the DNA fraction derived from tumor cells which could be applied as a non-invasive method for detecting tumor mutations before, during, and after therapies. Here, we reviewed most of the studies examining ctDNA as treatment monitoring in mCRC patients who receive different target therapies. Also, we compared ctDNA with other existing cancer-treatment monitoring methods.