New Prognostic Factors Associated with Long-term Survival in Node-Negative Breast Cancer Patients

Clinicopathological predictors of occult lateral neck lymph node metastasis in papillary thyroid cancer: A meta-analysis

BACKGROUND

This meta-analysis aimed to identify the clinicopathological factors that could predict the risk of occult lateral neck lymph node metastasis (OLLNM) in N0/N1a papillary thyroid cancer (PTC).

METHODS

A literature search of PubMed, Web of Science, OvidSP, and Chinese National Knowledge Infrastructure databases was performed using relevant keywords. Specific odds ratios and confidence intervals were calculated.

RESULTS

The final analysis included 15 studies with a total of 5342 patients. OLLNM was found to be significantly associated with some clinicopathological features, including age <45 years, male sex, extrathyroidal extension, tumor location in the upper pole, tumor size >10 mm, positive central lymph node metastasis, number of central lymph node metastasis ≥3, and vascular invasion.

CONCLUSIONS

Fine-needle aspiration (FNA) cytology or FNA-Tg test might be an appropriate and reasonable intervention in the patients with N0/N1a PTC with an increased risk of OLLNM.

Targeting the EGFR/PCNA signaling suppresses tumor growth of triple-negative breast cancer cells with cell-penetrating PCNA peptides

Tyrosine 211 (Y211) phosphorylation of proliferation cell nuclear antigen (PCNA) coincides with pronounced cancer cell proliferation and correlates with poor survival of breast cancer patients. In epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI)-resistant cells, both nuclear EGFR (nEGFR) expression and PCNA Y211 phosphorylation are increased. Moreover, the resistance to EGFR TKI is a major clinical problem in treating EGFR-overexpressing triple-negative breast cancer (TNBC). Thus, effective treatment to combat resistance is urgently needed. Here, we show that treatment of cell-penetrating PCNA peptide (CPPP) inhibits growth and induces apoptosis of human TNBC cells. The Y211F CPPP specifically targets EGFR and competes directly for PCNA tyrosine Y211 phosphorylation and prevents nEGFR from binding PCNA in vivo; it also suppresses tumor growth by sensitizing EGFR TKI resistant cells, which have enhanced nEGFR function and abrogated classical EGFR membrane signaling. Furthermore, we identify an active motif of CPPP, RFLNFF (RF6 CPPP), which is necessary and sufficient to inhibit TKI-resistant TNBC cell growth of orthotopic implanted tumor in mice. Finally, the activity of its synthetic retro-inverted derivative, D-RF6 CPPP, on an equimolar basis, is more potent than RF6 CPPP. Our study reveals a drug candidate with translational potential for the future development of safe and effective therapeutic for EGFR TKI resistance in TNBC.

Predictive factors for lateral occult lymph node metastasis in papillary thyroid carcinoma

Management of lateral no necks in papillary thyroid carcinoma (PTC) is very controversial. The aim of this study was to find predictive factors of lateral neck involvement in N0 PTC to help the clinician in his decision to treat the lateral compartment. We retrospectively analysed 173 patients who underwent thyroidectomy and lateral prophylactic neck dissection for PTC >10 mm. Predictive factors for occult lateral lymph node metastasis including sex, age, tumour size, multifocality and bilaterality, tumour extracapsular spread, vascular invasion and presence of a tumour capsule were examined by multivariate analysis. There were three independent predictive factors for occult lateral lymph node metastases in multivariate analysis: tumour extracapsular spread (p < 0.0001), vascular invasion (p < 0.001) and age <45 years (p < 0.027). When none of these factors was present, the risk of occult metastases was <5 %. The risk increased up to 56 % when at least two of these factors were present. These findings suggest that, in patients older than 45 years with neither tumour extracapsular spread nor vascular invasion on histopathological examination, occult lymph node metastases are very uncommon. In that case further discussion regarding the risks and benefits of lateral nodal dissection may be warranted.

Tyrosine phosphorylation controls PCNA function through protein stability

The proliferating cell nuclear antigen (PCNA) is an essential protein for DNA replication and damage repair. How its function is controlled remains an important question. Here, we show that the chromatin-bound PCNA protein is phosphorylated on Tyr 211, which is required for maintaining its function on chromatin and is dependent on the tyrosine kinase activity of EGF receptor (EGFR) in the nucleus. Phosphorylation on Tyr 211 by EGFR stabilizes chromatin-bound PCNA protein and associated functions. Consistently, increased PCNA Tyr 211 phosphorylation coincides with pronounced cell proliferation, and is better correlated with poor survival of breast cancer patients, as well as nuclear EGFR in tumours, than is the total PCNA level. These results identify a novel nuclear mechanism linking tyrosine kinase receptor function with the regulation of the PCNA sliding clamp.