Tumor Microenvironment, Clinical Features, and Advances in Therapy for Bone Metastasis in Gastric Cancer

PTH and the Regulation of Mesenchymal Cells within the Bone Marrow Niche

Parathyroid hormone (PTH) plays a pivotal role in maintaining calcium homeostasis, largely by modulating bone remodeling processes. Its effects on bone are notably dependent on the duration and frequency of exposure. Specifically, PTH can initiate both bone formation and resorption, with the outcome being influenced by the manner of PTH administration: continuous or intermittent. In continuous administration, PTH tends to promote bone resorption, possibly by regulating certain genes within bone cells. Conversely, intermittent exposure generally favors bone formation, possibly through transient gene activation. PTH's role extends to various aspects of bone cell activity. It directly influences skeletal stem cells, osteoblastic lineage cells, osteocytes, and T cells, playing a critical role in bone generation. Simultaneously, it indirectly affects osteoclast precursor cells and osteoclasts, and has a direct impact on T cells, contributing to its role in bone resorption. Despite these insights, the intricate mechanisms through which PTH acts within the bone marrow niche are not entirely understood. This article reviews the dual roles of PTH-catabolic and anabolic-on bone cells, highlighting the cellular and molecular pathways involved in these processes. The complex interplay of these factors in bone remodeling underscores the need for further investigation to fully comprehend PTH's multifaceted influence on bone health.

Radiologic patterns of distant organ metastasis in advanced breast cancer patients: Prospective review of computed tomography images

BACKGROUND

Breast cancer (BC) metastases to the abdomen and pelvis affect the liver, mesentery, retroperitoneum, peritoneum, bladder, kidney, ovary, and uterus. The study documented the radiological pattern and features of the chest, bone, abdominal and pelvic (AP) metastases among advanced BC patients.

AIM

The aim is to document the radiological pattern and features of breast cancer metastasis in the chest, abdomen, pelvis and bones.

MATERIALS AND RESULTS

Chest, abdominal, and pelvic computed tomography scan images of 36 patients with advanced BC were collated from Cape Coast Teaching Hospital and RAAJ Diagnostics. The images were prospectively assessed for metastasis to the organs of the chest, AP soft tissues, and bones. Radiologic features of metastasis of the lungs, liver, lymph nodes (LNs), and bones were documented. Patients' demographics, clinical data, and histopathology reports were also collected. The data were captured using UVOSYO and exported to Microsoft Excel templates. The data obtained were descriptively analyzed. Only 2.8% of BCs exhibited metaplastic BC, whereas 97.2% had invasive ductal BC. Triple-negative cases were 55.6%. Of 36 patients, 31 (86.1%), 21 (58.3%), and 14(38.8%) were diagnosed of chest, AP, and bone tissues metastasis, respectively. LN involvement was reported in 26 (72.2%) patients. Majority, 21 (58.3%) were diagnosed of multiple sites metastasis with 15 (41.7%) showing single site. Lungs (77.4%, 24/31) and liver (47.6%, 10/21) were the most affected distant organs. Most bone metastases were lytic lesions (92.9%, 13/14) with the vertebrae (85.7%, 12/14) been the most affected.

CONCLUSION

According to the study, advanced BC patients have a higher-than-average radiologic incidence of lung, liver, bone, and LN metastases.

Bone metastasis is a late-onset and unfavorable event in survivors of gastric cancer after radical gastrectomy: Results from a clinical observational cohort

Background

The timing and incidence of recurrent bone metastasis (BM) after radical gastrectomy in patients with gastric cancer (GC) as well as the survival of these patients were not fully understood. The aim of this study was to analyze the data of an observational GC cohort and identify patients who underwent curative gastrectomy and had recurrent BM to describe and clarify the pattern and profile of BM evolution after surgery.

Methods

Data were retrieved from a hospital-based GC cohort, and patients who underwent upfront radical gastrectomy were selected. The time points of specific organ metastatic events were recorded, and the person-year incidence rate of metastatic events was calculated. The latency period of BM events after gastrectomy was measured and compared with that of the other two most common metastatic events, liver metastasis (LM) and distant lymph node metastasis (LNM), using analysis of variance. Propensity score matching and subgroup analysis were used for sensitivity analysis.

Results

A total of 1324 GC cases underwent radical gastrectomy between January 2011 and December 2021. Of these, 67 BM, 218 LM, and 248 LNM occurred before the last follow-up. The incidence of BM events was 1.7/100 person-years, which was approximately 3-fold lower than that of LM and distant LNM events (5.5 and 6.3 per 100 person-years, respectively). BM events had a significantly longer latency (median time, 16.5 months) than LM and LNM events (11.1 and 12.0 months, respectively). Recurrent BM led to a worse prognosis (median survival, 4.5 months) than those of LM and LNM events (median survival, 7.7 and 7.1 months, respectively). However, no difference in overall survival after gastrectomy was observed among the groups.

Conclusions

Compared with other common metastatic events, BM in GC after gastrectomy is a late-onset event indicating poor survival.

Trial registration

No. ChiCTR1800019978; http://www.chictr.org.cn/.

Understanding the initiation, delivery and processing of bone cancer pain from the peripheral to the central nervous system

Bone cancer pain is a complex condition characterized by persistent, sudden, spontaneous pain accompanied by hyperalgesia that typically arises from bone metastases or primary bone tumors, causing severe discomfort and significantly diminishing cancer patients' quality of life and confidence in their ability to overcome the disease. It is widely known that peripheral nerves are responsible for detecting harmful stimuli, which are then transmitted to the brain via the spinal cord, resulting in the perception of pain. In the case of bone cancer, tumors and stromal cells within the bone marrow release various chemical signals, including inflammatory factors, colony-stimulating factors, chemokines, and hydrogen ions. Consequently, the nociceptors located at the nerve endings within the bone marrow sense these chemical signals, generating electrical signals that are then transmitted to the brain through the spinal cord. Subsequently, the brain processes these electrical signals in a complex manner to create the sensation of bone cancer pain. Numerous studies have investigated the transmission of bone cancer pain from the periphery to the spinal cord. However, the processing of pain information induced by bone cancer within the brain remains unclear. With the continuous advancements in brain science and technology, the brain mechanism of bone cancer pain would become more clearly understood. Herein, we focus on summarizing the peripheral nerve perception of the spinal cord transmission of bone cancer pain and provide a brief overview of the ongoing research regarding the brain mechanisms involved in bone cancer pain.

Galectin-1 promotes gastric cancer peritoneal metastasis through peritoneal fibrosis

BACKGROUND

Peritoneal metastasis is one of the main causes of death in patients with gastric cancer (GC). Galectin-1 regulates various undesirable biological behaviors in GC and may be key in GC peritoneal metastasis.

METHODS

In this study, we elucidated the regulatory role of galectin-1 in GC cell peritoneal metastasis. GC and peritoneal tissues underwent hematoxylin-eosin (HE), immunohistochemical (IHC), and Masson trichrome staining to analyze the difference in galectin-1 expression and peritoneal collagen deposition in different GC clinical stages. The regulatory role of galectin-1 in GC cell adhesion to mesenchymal cells and in collagen expression was determined using HMrSV5 human peritoneal mesothelial cells (HPMCs). Collagen and corresponding mRNA expression were detected with western blotting and reverse transcription PCR, respectively. The promoting effect of galectin-1 on GC peritoneal metastasis was verified in vivo. Collagen deposition and collagen I, collagen III, and fibronectin 1 (FN1) expression in the peritoneum of the animal models were detected by Masson trichrome and IHC staining.

RESULTS

Galectin-1 and collagen deposition in the peritoneal tissues was correlated with GC clinical staging and were positively correlated. Galectin-1 enhanced the ability of GC cells to adhere to the HMrSV5 cells by promoting collagen I, collagen III, and FN1 expression. The in vivo experiments confirmed that galectin-1 promoted GC peritoneal metastasis by promoting peritoneal collagen deposition.

CONCLUSION

Galectin-1-induced peritoneal fibrosis may create a favorable environment for GC cell peritoneal metastasis.