Bioprinted Human Lung Cancer-Mimics for Tissue Diagnostics Applications.

Developing a reproducible and secure supply of customizable control tissues that standardizes for the cell type, tissue architecture, and preanalytics of interest for usage in applications including diagnostic, prognostic, and predictive assays, is critical for improving our patient care and welfare. The conventionally adopted control tissues directly obtained from patients are not ideal because they oftentimes have different amounts of normal and neoplastic elements, differing cellularity, differing architecture, and unknown preanalytics, in addition to the limited supply availability and thus associated high costs. In this study, we demonstrated a strategy to stably produce tissue-mimics for diagnostics purposes by taking advantage of the three-dimensional (3D) bioprinting technology. Specifically, we take anaplastic lymphoma kinase-positive (Alk+) lung cancer as an example, where a micropore-forming bioink laden with tumor cells was combined with digital light processing-based bioprinting for developing native-like Alk+ lung cancer tissue-mimics with both structural and functional relevancy. It is anticipated that our proposed methodology will pave new avenues for both fields of tissue diagnostics and 3D bioprinting significantly expanding their capacities, scope, and sustainability.

Intertumoral Heterogeneity of CD3+ and CD8+ T-Cell Densities in the Microenvironment of DNA Mismatch-Repair-Deficient Colon Cancers: Implications for Prognosis.

PURPOSE: Colorectal cancers with deficient DNA mismatch repair (dMMR) are presumed to uniformly have dense lymphocytic infiltration that underlies their favorable prognosis and is critical to their responsiveness to immunotherapy, as compared with MMR-proficient (pMMR) tumors. We examined T-cell densities and their potential heterogeneity in a large cohort of dMMR tumors. EXPERIMENTAL DESIGN: CD3+ and CD8+ T-cell densities were quantified at the invasive margin (IM) and tumor core (CT) in 561 stage III colon cancers (dMMR, n = 278; pMMR, n = 283) from a phase III adjuvant trial (N0147). Their association with overall survival (OS) was determined using multivariable Cox analysis. RESULTS: Although CD3+ and CD8+ T-cell densities in the tumor microenvironment were higher in dMMR versus pMMR tumors overall, intertumoral heterogeneity in densities between tumors was significantly higher by 30% to 88% among dMMR versus pMMR cancers (P < 0.0001 for all four T-cell subtypes [CD3+IM, CD3+CT, CD8+IM, CD8+CT]). A substantial proportion of dMMR tumors (26% to 35% depending on the T-cell subtype) exhibited T-cell densities as low as that in the bottom half of pMMR tumors. All four T-cell subtypes were prognostic in dMMR with CD3+IM being the most strongly prognostic. Low (vs. high) CD3+IM was independently associated with poorer OS among dMMR (HR, 4.76; 95% confidence interval, 1.43-15.87; P = 0.0019) and pMMR tumors (P = 0.0103). CONCLUSIONS: Tumor-infiltrating T-cell densities exhibited greater intertumoral heterogeneity among dMMR than pMMR colon cancers, with CD3+IM providing robust stratification of both dMMR and pMMR tumors for prognosis. Potentially, lower T-cell densities among dMMR tumors may contribute to immunotherapy resistance.

Validation of a cell-cycle progression gene panel to improve risk stratification in a contemporary prostatectomy cohort.

PURPOSE: We aimed to validate a previously described genetic risk score, denoted the cell-cycle progression (CCP) score, in predicting contemporary radical prostatectomy (RP) outcomes. METHODS: RNA was quantified from paraffin-embedded RP specimens. The CCP score was calculated as average expression of 31 CCP genes, normalized to 15 housekeeper genes. Recurrence was defined as two prostate-specific antigen levels ≥ 0.2 ng/mL or any salvage treatment. Associations between CCP score and recurrence were examined, with adjustment for clinical and pathologic variables using Cox proportional hazards regression and partial likelihood ratio tests. The CCP score was assessed for independent prognostic utility beyond a standard postoperative risk assessment (Cancer of the Prostate Risk Assessment post-Surgical [CAPRA-S] score), and a score combining CAPRA-S and CCP was validated. RESULTS: Eighty-two (19.9%) of 413 men experienced recurrence. The hazard ratio (HR) for each unit increase in CCP score (range, -1.62 to 2.16) was 2.1 (95% CI, 1.6 to 2.9); with adjustment for CAPRA-S, the HR was 1.7 (95% CI, 1.3 to 2.4). The score was able to substratify patients with low clinical risk as defined by CAPRA-S ≤ 2 (HR, 2.3; 95% CI, 1.4 to 3.7). Combining the CCP and CAPRA-S improved the concordance index for both the overall cohort and low-risk subset; the combined CAPRA-S + CCP score consistently predicted outcomes across the range of clinical risk. This combined score outperformed both individual scores on decision curve analysis. CONCLUSION: The CCP score was validated to have significant prognostic accuracy after controlling for all available clinical and pathologic data. The score may improve accuracy of risk stratification for men with clinically localized prostate cancer, including those with low-risk disease.

Clarifying the diffuse gliomas: an update on the morphologic features and markers that discriminate oligodendroglioma from astrocytoma.

Diffuse gliomas are the most common brain tumors and include astrocytomas, oligodendrogliomas, and oligoastrocytomas. Their correct pathologic diagnosis requires the ability to distinguish astrocytic from oligodendroglial differentiation in histologic sections, a challenging feat even for the most experienced neuropathologist. Interobserver variability in the diagnosis of diffuse gliomas has been high owing to subjective diagnostic criteria, overlapping morphologic features, and variations in training and practice among pathologists. A select, albeit imperfect, group of molecular and immunohistochemical tests are available to assist in diagnosis of these lesions. Combined loss of chromosomes 1p and 19q is a genetic signature of oligodendrogliomas, whereas gains of chromosome 7 in the setting of intact 1p/19q are more typical of astrocytomas. Detection of amplified epidermal growth factor receptor favors the diagnosis of high-grade astrocytomas over anaplastic oligodendroglioma, which is especially relevant for small cell astrocytomas. Strong nuclear staining for p53 often reflects TP53 mutation and is typical of low-grade astrocytomas. The Olig family of transcription factors has not demonstrated their diagnostic usefulness. Diffuse gliomas remain a diagnostic challenge, and new markers are needed for proper classification and directed therapies.

Evaluation of p53 mutations in premalignant esophageal lesions and esophageal adenocarcinoma using laser capture microdissection.

p53 mutations have been implicated in the development of esophageal malignancies. The purpose of this study was to assess more accurately the incidence and types of p53 mutations in Barrett's esophagus (BE) with and without dysplasia and in esophageal adenocarcinoma, using pure preparations of epithelial cells obtained by laser capture microdissection (LCM). Assays were performed on paraffin-embedded tissue samples of normal antrum and premalignant and malignant esophageal samples from 57 patients, including 16 controls, 10 with BE metaplasia alone, 20 with BE-associated dysplasia, and 11 with BE-associated adenocarcinoma. All tissues were processed for LCM. DNA was extracted from isolated cells, and polymerase chain reaction (PCR) was performed using oligonucleutide primers for exons 5-8 of p53. PCR products were processed for DNA sequencing. p53 sequence abnormalities were identified in 2/16 cases of normal antrum and regenerative/chemical gastritis, 1/10 cases of BE, 1/20 cases of BE with dysplasia, and 2/11 cases of adenocarcinomas. The abnormalities occurred in exons 7 and 8 in the form of point mutations. Our results, using LCM, show that p53 gene mutations are relatively rare in esophageal preneoplastic and neoplastic conditions. Only point mutations were detected, but no deletions/insertions were identified.