Aggressive undifferentiated colon carcinoma producing granulocyte-colony stimulating factor: report of a case

TLR5 agonists enhance anti-tumor immunity and overcome resistance to immune checkpoint therapy

Primary and adaptive resistance to immune checkpoint therapies (ICT) represent a considerable obstacle to achieving enhanced overall survival. Innate immune activators have been actively pursued for their antitumor potential. Herein we report that a syngeneic 4T1 mammary carcinoma murine model for established highly-refractory triple negative breast cancer showed enhanced survival when treated intra-tumorally with either the TLR5 agonist flagellin or CBLB502, a flagellin derivative, in combination with antibodies targeting CTLA-4 and PD-1. Long-term survivor mice showed immunologic memory upon tumor re-challenge and a distinctive immune activating cytokine profile that engaged both innate and adaptive immunity. Low serum levels of G-CSF and CXCL5 (as well as high IL-15) were candidate predictive biomarkers correlating with enhanced survival. CBLB502-induced enhancement of ICT was also observed in poorly immunogenic B16-F10 melanoma tumors. Combination immune checkpoint therapy plus TLR5 agonists may offer a new therapeutic strategy to treat ICT-refractory solid tumors.

G-CSF/GM-CSF-induced hematopoietic dysregulation in the progression of solid tumors

There are two types of abnormal hematopoiesis in solid tumor occurrence and treatment: pathological hematopoiesis, and myelosuppression induced by radiotherapy and chemotherapy. In this review, we primarily focus on the abnormal pathological hematopoietic differentiation in cancer induced by tumor-released granulocyte colony stimulating factor (G-CSF) and granulocyte-macrophage colony stimulating factor (GM-CSF). As key factors in hematopoietic development, G-CSF/GM-CSF are well-known facilitators of myelopoiesis and mobilization of hematopoietic stem cells (HSCs). In addition, these two cytokines can also promote or inhibit tumors, dependent on tumor type. In multiple cancer types, hematopoiesis is greatly enhanced and abnormal lineage differentiation is induced by these two cytokines. Here, dysregulated hematopoiesis induced by G-CSF/GM-CSF in solid tumors and its mechanism are summarized, and the prognostic value of G-CSF/GM-CSF-associated dysregulated hematopoiesis for tumor metastasis is also briefly highlighted.

Paraneoplastic leukemoid reaction: Case report and review of the literature

OBJECTIVES

We recently encountered a patient with unexplained hyperleukocytosis (105.4 K/μL at presentation), subsequently found to have colon cancer with a marked tumor-associated neutrophilic infiltrate; the leukocytosis abruptly improved after tumor removal. Paraneoplastic leukemoid reaction (PLR) is a rare entity, occurring due to tumor cytokine secretion (typically granulocyte-colony stimulating factor [G-CSF]). We describe a case and aggregate results of previously published cases.

METHODS

We reviewed the English-language literature for all prior reports of PLR, recording age, gender, histologic diagnosis, WBC count, G-CSF level, and overall survival. We analyzed clinicopathologic variables' impact on survival.

RESULTS

We identified 179 cases (mean age 64; 72 % M). Adeno-, squamous cell, sarcomatoid, and undifferentiated carcinomas accounted for >70 %. Esophagus, gallbladder, lung, liver, and pancreas were the most common primaries. At time of publication 81 % of patients had died, with mean overall survival of 4 months. There was no correlation between WBC count and G-CSF level. On univariate analysis, WBC count was the only variable associated with survival (P = 0.03). Patients with WBC counts >100 K/μL were twice as likely to die as those with counts from 11 K to 40 K/μL.

CONCLUSIONS

PLR, typically carcinoma-associated, is characterized by dismal prognosis. The WBC count is inversely related to survival. Knowledge of this phenomenon militates against protracted, expensive work ups. In malignant neoplasms with prominent neutrophilic stroma, the pathologist should correlate with the WBC count and, if markedly elevated (>40 K/μL), raise consideration for PLR.

A role for G-CSF and GM-CSF in nonmyeloid cancers

Granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) modulate progression of certain solid tumors. The G-CSF- or GM-CSF-secreting cancers, albeit not very common are, however, among the most rapidly advancing ones due to a cytokine-mediated immune suppression and angiogenesis. Similarly, de novo angiogenesis and vasculogenesis may complicate adjuvant use of recombinant G-CSF or GM-CSF thus possibly contributing to a cancer relapse. Rapid diagnostic tools to differentiate G-CSF- or GM-CSF-secreting cancers are not well developed therefore hindering efforts to individualize treatments for these patients. Given an increasing utilization of adjuvant G-/GM-CSF in cancer therapy, we aimed to summarize recent studies exploring their roles in pathophysiology of solid tumors and to provide insights into some complexities of their therapeutic applications.

Expression of CD163 prevents apoptosis through the production of granulocyte colony-stimulating factor in meningioma

BACKGROUND

CD163 is a 130-kDa transmembrane protein expressed in human monocytes and macrophages, and the aberrant expression of CD163 in breast and colorectal cancer associated with patients' poor prognosis was reported. Here, we analyzed the expression of CD163 in meningioma, a common intracranial tumor, and its molecular mechanism in association with meningioma progression.

METHODS

First, we performed immunohistochemical analysis using 50 human meningioma specimens. Next, we established CD163-overexpressing human meningioma cell lines and investigated its roles in tumor progression in vitro and in vivo.

RESULTS

Immunohistochemically, 26 of 50 human meningioma specimens (52.0%) were positive for CD163 in tumor cells, including benign grade I (48.5%) and grade II (71.4%) cases. Furthermore, CD163 expression was correlated with histological atypical parameters that directly predict the prognosis of meningioma. CD163-overexpressing meningioma cells showed significant suppression of apoptosis and accelerated tumor growth in nude mice. In addition, unexpected splenomegaly affiliated with the xenograft predicted tumor-derived granulocyte colony-stimulating factor (G-CSF) production, which was confirmed by reverse-transcription polymerase chain reaction and enzyme-linked immunosorbent assay.

CONCLUSIONS

To our knowledge, this is the first report that demonstrates CD163 expression in meningioma not only by immunohistochemistry but also by reverse-transcription polymerase chain reaction, using primary culture cells, and provides the novel molecular function of CD163 to prevent apoptosis through the production of G-CSF in meningioma.