Esophageal Cancer-Derived Organoids to Predict Patients' Treatment Response

PURPOSE/OBJECTIVE(S)

The absolute 10-year overall survival of esophageal adenocarcinoma (EAC) has significantly increased from 26% to 36% due to neoadjuvant chemoradiotherapy (nCRT) with consecutive radical resection. However, 20-25% of EAC patients don't respond to nCRT and need alternative treatment, and 20-30% have a complete pathological response and may not need resection. Therefore, there is an urgent need for better models to accurately predict response of EAC to nCRT. Accumulating evidence indicates that patient-derived organoids (PDOs) may predict treatment responses, but the ability of PDOs to predict responses to chemoradiation in EAC patients remains unknown. Hence, we generated patient derived EAC cancer organoids (ec-PDOs) to examine their response to nCRT.

MATERIALS/METHODS

The biopsies from treatment-naïve EAC patients after informed consent were used to establish ec-PDOs. Next, we investigated the response of ec-PDOs to the components of standard-of-care neoadjuvant treatment, including irradiation, carboplatin, and paclitaxel. Finally, the potential of ec-PDOs to reflect patients' response to nCRT before esophageal resection was evaluated.

RESULTS

Mechanically and enzymatically dispersed patient derived EAC biopsies were cultured as ec-PDOs for up to 10 passages, indicating the self-renewal and expansion potential. These ec-PDOs expressed the EAC marker MUC5AC, indicating the EAC origin. Differences in growth kinetics and response to irradiation, carboplatin, and paclitaxel were observed between patients specific ec-PDOs. However, similar dose-response curves were seen within ec-PDOs from the same patient after different passages. This indicates that ec-PDOs exhibit interpatient response heterogeneity but have good reproducible responses within the same patient. Moreover, after combined treatment with irradiation (IR), carboplatin (Car), and paclitaxel (Pac) to mimic nCRT in EAC patients, the stem cell survival of ec-PDOs from patients with complete response (CR) and partial response (PR) are lower than that from those with progressive disease (PD).

CONCLUSION

The preliminary findings in this study suggest a great potential of ec-PDOs to predict patient-specific responses to neoadjuvant treatment in EAC patients.

Thyroid Gland Organoids: Current models and insights for application in tissue engineering

The incidence of treatment of thyroid disease and consequential hypothyroidism has been increasing over the past few years. To maintain adequate thyroid hormone levels, these patients require daily supplementation with levothyroxine (L-T4) for the rest of their lives. However, a large part of these patients experiences difficulties due to the medication, which causes a decrease in their quality of life. Regenerative medicine through tissue engineering could provide a potential therapy by establishing tissue engineering models, such as those employing thyroid-derived organoids. The development of such treatment options may replace the need for additional hormonal replacement therapy. This review aims to highlight the current knowledge on thyroid regenerative medicine using organoids for tissue engineering, and to discuss insights into potential methods to optimize thyroid engineering culture systems. Finally, we will describe several challenges faced when utilising these models.

Value of RT-PCR analysis of sentinel nodes in determining the pathological nodal status in colon cancer

BACKGROUND

Pathological examination of sentinel lymph nodes (SLNs) and non-SLNs in colon cancer is frequently not performed to the same extent. We examined whether non-SLNs were truly negative in tumors with tumor-negative SLNs using reverse transcriptase-polymerase chain reaction (RT-PCR).

PATIENTS AND METHODS

RT-PCR with carcinoembryonic antigen (CEA) was performed in hematoxylin-eosin (H&E) and immunohistochemical (IHC) tumor-negative SLNs. In RT-PCR negative SLNs, we also performed RT-PCR on non-SLNs. Statistical analyses indicated the requirement for a minimum of 72 accurate comparisons of non- SLNs and SLNs, which could be fulfilled using tissues from 12 patients.

RESULTS

Negative and positive controls were performed. In nine of the 12 colon tumors, H&E and IHC-negative SLNs were also negative with CEA-RT-PCR. A total of 102 lymph nodes, including 99 non-SLNs were retrieved in these nine specimens and none of the non-SLNs were CEA RT-PCR-positive.

CONCLUSION

In this study, all CEA RT-PCR tumor-negative SLNs correctly reflect the tumor-negative status of the non-SLN's in primary colon tumors. The reliability of this method in colon cancer seems promising.

Prognostic role of cyclooxygenase-2 expression in esophageal carcinoma

Cyclooxygenase-2 (COX-2) is involved in esophageal carcinogenesis, but its clinical significance is not clarified yet. The association of several clinicopathological parameters with the immunohistochemical expression of COX-2 was analyzed in paraffin-embedded esophageal cancer specimens. In adenocarcinomas, COX-2 upregulation showed to be a late event and in a multivariate analysis it was associated independently with a reduced survival after surgery compared with low COX-2 expressed tumors (P=0.02). Although, the expression was extensively high in well-differentiated parts of squamous cell carcinoma, it was not related with a poor outcome. This study supports further investigation of selective COX-2 inhibitors in these tumors.