Chemotherapy and Targeted Agents in the Treatment of Elderly Patients with Metastatic Colorectal Cancer

Optimizing the first-line treatment for metastatic colorectal cancer

Colorectal cancer represents an important oncological challenge both for its incidence, which makes it an important health problem, and for its biological complexity, which has made clinical results very difficult in terms of outcome for this category of patients. To date these diseases should not be treated as a single entity but it is necessary to distinguish colorectal cancers based on characteristics that nowadays are essential to have greater therapeutic benefits. These include the sideness of the disease, the state of microsatellites, the presence of prognostic and predictive mutations of response to treatments currently available in clinical practice, which are associated with new therapeutic targets. The greatest challenge in the future will be to circumvent the resistance mechanisms that make this disease very difficult to treat with good long-term results by studying effective combination treatments with a good toxicity profile. Once such combinations or targeted treatments are consolidated, it will be desirable to shift the best therapies to the first line treatment to make them immediately accessible to the patient. It will also be essential to refine the selection of patients who can benefit from these treatments.

Presentation, Molecular Characteristics, Treatment, and Outcomes of Colorectal Cancer in Patients Older than 80 Years Old

Background: An increasing proportion of the population of patients with cancer presents at an advanced age, increasing the challenges of successful and well-tolerated treatments. In the older spectrum of the geriatric cancer patients, those older than 80 years old, challenges are even higher because of increasing comorbidities and decreasing organ function reserves. Methods: Studies regarding colorectal cancer presentation, treatment, and prognosis in patients older than 80 years old available in the literature were evaluated and were compiled within a narrative review. Molecular attributes of colorectal cancer in the subset of patients older than 80 years old in published genomic cohorts were also reviewed and were compared with similar attributes in younger patients. Results: Characteristics of colorectal cancer in octogenarians are in many aspects similar to younger patients, but patients older than 80 years old present more often with right colon cancers. Surgical treatment of colorectal cancer in selected patients over 80 years old is feasible and should be pursued. Adjuvant chemotherapy is under-utilized in this population. Although combination chemotherapy is in most cases not advisable, monotherapy with fluoropyrimidine derivatives is feasible and efficacious. Conclusions: Outcomes of colorectal cancer patients over the age of 80 years old may be optimized with a combination of standard treatments adjusted to the individual patient's functional status and organ reserves. Increased support for the older age group during their colorectal cancer treatment modalities would improve oncologic outcomes with decreasing adverse outcomes of therapies.

RNA demethylase ALKBH5 suppresses tumorigenesis via inhibiting proliferation and invasion and promoting CD8+ T cell infiltration in colorectal cancer

BACKGROUND

ALKBH5 belongs to the ALKB family consists of a Fe (II) and a-ketoglutarate-dependent dioxygenase. ALKBH5 directly catalyzes the oxidative demethylation of m6A-methylated adenosine. ALKBH5 involves in tumorigenesis and tumor progression, and is often dysregulated in a wide range of cancers, including colorectal cancer. Emerging evidence indicates that the expression of ALKBH5 is associated with the abundance of infiltrating immune cells in the microenvironment. However, how ALKBH5 affects immune cell infiltration in the microenvironment in colorectal cancer (CRC) has not been reported. The aim of this study was to identify how the expression of ALKBH5 affects the biological behaviors of CRC cell lines and regulates the effects on infiltrating CD8⁺ T cells in CRC microenvironment with its specific mechanism.

METHODS

Firstly, the transcriptional expression profiles of CRC were downloaded from TCGA database and integrated via R software (4.1.2). Between CRC and normal colorectal tissues, ALKBH5 mRNA expressions were compared (Wilcoxon rank-sum). We further identified the expression levels of ALKBH5 in CRC tissues and cell lines through quantitative PCR, western blot, and immunohistochemistry. Then, how ALKBH5 affects the biological behaviors of CRC cells were confirmed by gain- and loss-of-function analysis. Furthermore, the relationship between ALKBH5 level and 22 tumor-infiltrating immune cells was examined through CIBERSORT in R software. Furthermore, we explored the correlation between ALKBH5 expression and tumor-infiltrated CD8⁺, CD4⁺ and regulatory T cells by utilizing the TIMER database. Finally, the association between chemokines and CD8⁺ T cells infiltration in CRC was analyzed using GEPIA online database. qRT-PCR, WB and IHC were used to further determine the effect of ALKBH5 on NF-κB-CCL5 signaling axis and CD8⁺ T cells infiltration.

RESULTS

Clinically, ALKBH5 expression was downregulated in CRC and low levels of ALKBH5 expression were correlated with poor overall survival (OS). Functionally, overexpression of ALKBH5 reduced the proliferation, migration and invasion of CRC cells, and vice versa. Overexpression of ALKBH5 suppresses NF-κB pathway, thus reduces CCL5 expression and promotes CD8⁺ T cells infiltration in CRC microenvironment.

CONCLUSIONS

ALKBH5 is poorly expressed in CRC, and overexpression of ALKBH5 attenuates CRC malignant progression by inhibiting CRC cell proliferation, migration, invasion and promoting CD8⁺ T cells infiltration in the tumor microenvironment through NF-κB-CCL5 axis.

Trifluridine/tipiracil (FTD/TPI) and regorafenib in older patients with metastatic colorectal cancer

Colorectal cancer is a disease of older patients, but few guidelines directly address age in their recommendations. Older patients may present comorbidities that affect the choice of chemotherapy, and care must be taken when choosing the best approach. This narrative review aimed to describe the literature regarding approved oral agents for third-line treatment in older patients with refractory metastatic colorectal cancer, regorafenib, and trifluridine/tipiracil (FTD/TPI).

Efficacy and Safety of Local Radiotherapy to All Oligometastatic Sites in Elderly Patients with Metachronous Oligometastatic Cancers After Initial Treatment for the Primary Tumor

Background and Purpose

This study aimed to investigate the efficacy and safety of maintenance therapy combined with local radiotherapy at all oligometastatic sites (LRTOS) in elderly patients with metachronous oligometastatic cancers (MOC).

Patients and Methods

A total of 242 elderly patients with MOC (≤5 metastases) and primary tumor well controlled after definitive treatment was retrospectively analyzed between August 2014 and February 2020 at Beijing Geriatric Hospital and Air Force General Hospital. Patients were divided into maintenance therapy group (maintenance therapy alone) and local radiotherapy group (maintenance therapy combined with LRTOS).

Results

There were 86 patients in the local radiotherapy group and 156 patients in the maintenance therapy group. The median length of follow-up was 36 months (range, 8.0–62 months). Median overall survival (mOS) was 25 months (95% CI: 21.1–28.9) in the local radiotherapy group and 16 months (95% CI: 14.5–17.6) in the maintenance therapy group (p < 0.001). Multivariate analyses demonstrated that LRTOS (hazard ratio (HR) = 0.49, 95% confidence interval (CI): 0.35–0.67, p < 0.001), good Eastern Cooperative Oncology Group Performance Status (ECOG PS, HR = 0.69, 95% CI: 0.49–0.97, p = 0.032), longer duration between diagnosis of primary tumor and occurrence of progression (HR = 0.87, 95% CI: 0.78–0.97, p = 0.015), and subsequent systemic treatment (HR = 0.52, 95% CI: 0.38–0.72, p < 0.001) were independent predictors of good OS. In patients who did not receive subsequent systemic treatment, their mOS was 21 months (95% CI: 12.8–29.2) for those treated with LRTOS and 14 months (95% CI: 11.4–16.6) for those who did not receive local radiotherapy (p = 0.001). Further multivariate analysis showed that LRTOS was the only independent factor for predicting good OS (HR = 0.47, 95% CI: 0.26–0.83, p = 0.010). Patients with metachronous oligometastatic lung cancer, colorectal cancer, prostate cancer, and breast cancer had higher survival benefits following LRTOS. Most patients suffered from grade 1–2 toxicities, but no treatment-related death was recorded.

Conclusion

This retrospective study shows that elderly patients with MOC treated with LRTOS may have better survival outcomes.

Deliver protein across bio-barriers via hexa-histidine metal assemblies for therapy: a case in corneal neovascularization model

Because of their high specificity and low side effects, protein drugs possess a substantial global market. However, the low bioavailability of protein is still a major obstacle to their expanded applications, which is expected to be answered with proper protein formulations. Taking corneal neovascularization (CNV) as an example, we demonstrated a co-assembled system of hexa-histidine and Ava (Avastin) with metal ions (HmA@Ava) could cross the cornea, the most important bio-barrier during the treatment of most diseases of the anterior segment in clinics. We found that the nanosized HmA@Ava efficiently encapsulated Ava with impressive loading capacity without destroying the bioactivity of Ava and assisted Ava penetration through the corneal barriers to effectively inhibit CNV development in an alkali burn rat model with sustained and pH-dependent Ava release. Our results suggested that the co-assembled strategy of protein and HmA is a proper formulation to protein drugs, with promising penetration ability to deliver protein across bio-barriers, which could open a path for topical administration of protein drugs for treatment of various ocular diseases and hold enormous potential for delivery of therapeutic proteins not only for ocular diseases but also for other diseases that require protein treatment.

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HmA@Ava can bring protein drug, Ava, across over the primary bio-barrier of the anterior segment ​and efficiently treat CNV.

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HmA@Ava was nanoparticles, with impressive loading capacity without destroying bioactivity of Ava ​and strong pH-dependent release.

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HmA can open a path for the treatment of eye diseases and hold huge potential to protein drugs to other diseases.

Management of Metastatic Colorectal Carcinoma in Older Adults: Balancing Risks and Benefits of Novel Therapies

The prevalence of older patients with metastatic colorectal cancer (mCRC) will continue to increase with our aging population. Treatment of mCRC has changed significantly in the last few decades as we have learned how to personalize the treatment of mCRC to the biology of the tumor, utilizing new treatment approaches. With an ever-changing treatment paradigm, managing the population of older adults becomes paramount. This review highlights the pivotal clinical trials that defined the use of systemic therapy, immunotherapy and targeted therapies for mCRC, and how those are applied to the older patient population. In addition, we outline the tools for an in-depth assessment of an older adult in regards to treatment planning and management of therapy-related toxicities. A comprehensive geriatric assessment can assist in the selection of treatment for an older adult with mCRC. While frail older patients can frequently only tolerate single agents or modified regimens, fit older adults remain candidates for a wider range of treatment options. However, since all of these treatments are associated with possible toxicities, each patient's treatment must be personalized to the patient's goals and wishes through a shared decision-making process.